Mercedes Sprinter Turbo – Limp Home – Diagnosis and Fault Finding

Mercedes Sprinter Turbo – Limp Home (LHM) Diagnostics.

You will probably read a great deal on the internet regarding the issues surrounding your Sprinter lapsing into limp-home mode without showing any EML (Engine Management Warning Lamp).  I have also read these web entries with interest and have concluded that there is a lot of confusion around what exactly is going on so I have decided to add my own input so that hopefully you can sort out this irritating and troublesome issue.

The early Sprinters with vac controlled turbo actuators are quite basic in operation and there are only a few elements to the control loop.  These can all be checked out systematically and the faulty element identified and replaced/repaired.

Let me try and explain in basic terms how the turbo control system works so that you may get a better understanding of what is going on:

VNT Turbo and Vacuum Actuator (sometimes known as a VGT Turbo)

Sprinter Vacuum Boost Actuator

Sprinter Vacuum Boost Actuator

The turbo itself is a Garrett VNT variable vane turbo, the details of which you will find elsewhere on this site. ( ) It is controlled by a vacuum actuator that moves a set of mechanical vanes within the turbo to vary the turbo charge rate – there is no conventional dump valve on these turbos and many times you will wrongly read people refer to it as the ‘dump valve actuator’.   The charge actuator resides bolted to the turbo body on an extended bracket, its push rod connects to a small lever that enters into the turbo body casting, moving a small lever shaped rather like a dog-bone.  This lever engages in an annular ring that in turn interlaces with a set of similar levers attached to each variable vane. A single action of pushing or pulling the actuator rod moves all the vanes inside the turbo in unison, developing more or less turbo charge dependant on its position.  Inspect the external lever that the actuator push rod attaches to, ensure this moves smoothly as you accelerate / rev the engine.  Look for any misalignment of the lever throughout its stroke as it passes through the turbo body, as the bearing surfaces on this shaft can wear or oval allowing the internal lever to ride over the annular ring inside resultantly not moving any of the vanes.  A quick and dirty test to indicate any problems with the variable vanes is to remove the air box or air filter housing and listen as the engine is revved.  Once the engine is started, the vac actuator rod should move down slowly as vac builds, this in turn should apply force to the lever moving the vanes into a fully charged position.  As you rev the engine you should hear a very loud and strong tornado type howl from the air box, if you do not, and the actuator has moved pulling the lever downward there is a chance that the turbo itself is faulty.  Normal operation is as follows.  Stationary engine, rod fully extended, vanes in no charge position. Start engine, rod pulls lever downward slowly, vanes full charge position.  Rev engine, rod moves in and out during the rev cycle, vanes apply variable charge through rev cycle – Audible howl from air box.

Turbo Actuator Electric Vacuum Control Valve

Sprinter Boost Actuator Valve

Sprinter Boost Actuator Valve

If the vacuum actuator is not pulling down once the engine is started check for vac at the pipe, if vac is present, the actuator could be seized or faulty (internal diaphragm split) rectify this.  If you follow the vac pipe back from the turbo you will see that it goes to an actuator that is bracket mounted on the inner wing below the air box at the back of the off side headlamp (UK Vehicles)  This can be pulled upward off its bracket mounting rubber and moved to a better place for visual inspection.  This electrical valve actuator is popularly at fault with the Mercedes Sprinter model and your dealer will have sold hundreds of this item over time.  It has a single two wire electrical plug connected to it and three rubber pipes; in some cases its pipe locations are even marked: IN – OUT – VENT.  Check vac supply to this device observing and rectifying any split or leaking pipework.  Once good vacuum supply has been determined, with the ignition off (no power to the valve and no vacuum present) the route of vacuum should be blocked by the valve to the turbo actuator.  The turbo actuator supply pipe should be vented to atmosphere via the electric control valve to a small filter (looks like in-line fuel filter) mounted above the engine and sitting by the side of the brake servo.

sprinter vacuum diagram

Turning on the ignition places a constant 12v to the electrical controlled vac actuator valve, (This voltage pulses during normal engine operation)  vac should now be routed from actuator valve inlet to the turbo actuator (outlet) and the vent should now be blocked.   Vacuum switching can be verified by using  a hand vac pump (Mytivac or similar) Simply sucking on the pipes will not prove anything, as there is an internally sprung pressure control diaphragm inside the electronic valve so that operation will not occur until sufficient vac is present –  the only thing you will achieve by sucking with your mouth – is a red face!  An old Mercedes engineer once shared that there are two versions of the electric vacuum valve available, one with a blue cap and the other with a black cap, only the matching type should be used as a replacement.  I cannot verify this information as I have only ever seen the black cap type, but best practice would suggest replacing the unit only with the correct version to be 100% on the safe side.

Relevant Service Manual Extract View Here

ECU Control

The ECU control loop circuit is quite simple for turbo actuation.  The electric vac valve is controlled by simply switching the 12v supply on and off by the ECU, this is called PWM or Pulse Width Modulation – it’s easy to test this control voltage is present with a volt meter at the valve electrical plug/connector with ignition on.  If no control voltage is present look for a break in the wiring from the valve to the ECU.  Trace back the wires to the ECU connector and prove continuity exists from the ECU connector to the valve.  Pin outs and wire colours are given in the included diagrams.  There has been commonly reported breaks in the valve supply wiring as it is routed in front of the intercooler behind the grille and also in the area of the near side headlamp where the loom kinks back into the engine bay around the radiator. The wire colours to look for here are white and blue (on my model) but please check the included diagram/chart for correct model notation.

Relevant Service Manual Extract View Here – Wiring Identification at ECU – Turbo Boost

ECU General

Remove the ECU from its slide tray under the passenger dash area beneath the glove box area.  It is quite common for the bulkhead grommet to displace where the main ECU loom is routed to the engine bay allowing water to enter and run down onto the ECU connectors.  Remove all the connector attachments to the ECU and check for pin corrosion, if this exists clean up both the pin and connectors as best you can.  Importantly – reseat the bulkhead grommet.

Charge Pressure Sensor / Intake Air Temperature Sensor

Sprinter Boost Pressure Sensor Location

Sprinter Boost Pressure Sensor Location

There are two sensors in the control loop, a pressure sensor and an air temperature sensor.  They are identified as one having three or sometimes four wires (commonly three) this is the charge pressure sensor. The second is intake air temperature sensor having two wires.  They are both located in the upper section of the intercooler discharge hose, on the near side of the vehicle (UK versions) on the hard moulded plastic section of ductwork before the final supply hose to the inlet manifold, just to the side of the radiator.  The pressure sensor is attached to the housing with two small bolts.  The connections to this device are again simple to understand and test.  One of the three wires is ground, the second is 5v+ve supply and the other connection gives an approximate variable voltage output +0.2v to +5v referenced to ground dependant on charge pressure.  The other sensor (air temperature) is found slightly lower down the plastic section of pipework, this measures charge intake air temperature. This has a two wire connection that is connected across an internal thermistor bead that feeds back a change in resistance value relative to air temperature inside the inlet pipework, the two connected wires are fed through the bulkhead, directly back to the ECU along with those from the pressure sensor.  The temperature sensor should measure between 400 and 500 Kilo-Ohms out of circuit.  In the information given it is possible to plot the output from the charge pressure sensor to give an indication of charge pressure in the system, from this you can derive if it functioning correctly or if to suspect it as faulty.  If you need to measure what is going on in-circuit without disconnecting these components, take a number of drapery pins and push them through the insulation into the conductor cores of the required wires thus allowing you to connect a test meter and take measurements without the need to disconnect or cut any wires.

Relevant Service Manual Extract View Here – Sprinter Boost Pressure Sensor

You can disconnect any of these components without lighting the EML warning lamp as no indication of a fault is given by the removal of any of these components from circuit.  That is why the dreaded turbo limp home fault often occurs without any indication on the dashboard.

Rev Limiter Function

Normally Sprinter engine revs are ECU limited whilst stationary to around 3500 rpm. Depressing the clutch and then further releasing it should now allow revs to increase above this range to the rev limit. If there is a limp home fault, engine revs will not progress above 3000 rpm even when dipping/releasing the clutch when stationary. Once the fault is rectified the rev range and limiter function as described above will return to normal.  It is a good idea to check out both of the necessary brake and clutch pedal position switch sensors (on the pedal box above the clutch and brake) and where possible always get hold of a compatible diagnostic code reader as often faults are stored and not indicated with a EML lamp.

I hope this helps you to better understand the function of the turbo boost circuit on early model Mercedes Sprinters and that it assists you to fault find and rectify any problems you may have.

729 thoughts on “Mercedes Sprinter Turbo – Limp Home – Diagnosis and Fault Finding

  1. 2002 313cdi. Hi All-please help
    New turbo fitted, if you dive in traffic and say in third gear revs fall under 2000 rpm as soon as you you depress accelerator pedal it goes into limp mode. The boost control sensor has been replaced by MB but the problem is not solved. All the vacuum pipes has been checked, MB updated software on computer.
    It even goes into limp mode on the highway. Once you switch engine of and on it goes again .I’f spent 1000s of rands but no success ,please can someone help. The MB mechanic is now waiting for answers from germany

    1. Hi there Dreyer,

      You really need to see what is happening to the boost pressure under these fault conditions using ‘live-data’. It sounds most probable that the ecu is cutting into limp mode because of either an under or overboost condition. Please have a look at this post and importantly the comments as there is some info hidden in here too. My gut feeling is that once you can monitor exactly what is going on with the manifold pressure, post-turbo, you should be able to draw firm conclusions as to if adjusting the actuator rod length and so the amount of boost at certain engine rpm/load, will help your situation – my own view is that it may just be the issue here !

      All the best

      1. We all though Mercedes Benz meant quality!!!!!!!!!!!!.

        1 out of 5, reviewed on Nov 24, 2016

        We all though Mercedes Benz meant quality.
        I am interested in collecting owner information of those individuals or companies who have had major expenses & Faults in maintaining Mercedes Benz Sprinters, who would be interested in being included in a class action law suit again Mercedes Australia. David 0429 999 958
        Only 6 of the 275 Sprinter owners I spoke to so far would recommend to buy a Mercedes Sprinter van again. They are Poor quality Sprinter van. I am on my 2nd “Lemon” Mercedes Sprinter! My first van had been towed 10 times during the

        first 8,000 kms. And this was my fifth harmonic balancer to be replaced and would take another 4 days?! When I purchased a brand new Mercedes Sprinter van I was immediately faced with continuous faults, break downs and issues with the engine and the mechanical working of the vehicle. After months of Cricks mechanics working on my vehicle and replacing parts constantly due to many different mechanical issues.

  2. Hi there I have a 2008 spinter 311cdi UK van I bought it in limp mode I see the turbo actuator is electric and it does not move when you start the engine the lever on the turbo moves good when the actuator is disconnected is this because we are in limp mode thanks pat Kelly ireland

    1. Hi Pat,
      Yes, the fact it fails to move is a result of the ECU holding it off, as you say it is probably in limp mode. First port of call is get a comprehensive code read done using a Mercedes Star diagnostic tool (or Chinese clone) This will give you an idea where the problem lies, you are best to clear all the codes once noted and see what comes back, working from that point on is the most logical approach.
      All the best

  3. Hi Dreyer and Steve
    being having the same issue on my 2013 Sprinter. I am in USA and i drove 300 miles and as i drove off the freeway and stopped at the robot(traffic light) van went into limp mode. Shut the engine off restarted after a couple of minutes and it was ok but a couple of miles down the road it happened again.
    this was 2 days ago and its has not happened again.
    its frustrating that MB has not found a solution to this problem. its not as if i was over taxing the motor as i was driving speed limit of 65/70 miles per hr. i did have air con on and was using cruise control for a fair amount of the time. do i need to “rest” the van every 100 or so miles?
    your feedback will be most welcome.

    1. Hi Allen,
      There are two very common scenarios to the Issues seen, one is the EGR valve either sticks open slightly porting turbo boost straight from the inlet down the exhaust pipe, or a problem with the turbo. On UK 4 cyl models the twin turbo (to about 2009 MY) was known to have sticking actuator mechanisms, Often associated to heat. This caused either under or overboost limp home that went away after a period of cooling off. I cant remember if this was internal or external, anyway an MB modified unit became available to replace the complete assembly. Obviously the EGR valve is subject to the same variance in temperature as other engine components and can stick open as a result if faulty. Often cleaning this will prove or disprove the fault, it is simple to do and if there is a noticeable difference after doing so, then often fitting a new EGR will rectify the problem. A code read from a MB agent or independent dealer should help you pinpoint the faults more certainly – as limp home is the result (MB engine protection mechanism) of many issues and problems with this engine it is necessary to use the diagnostics to help guide your wallet!
      All the best

  4. Buenos dias, tengo el mismo problema con el turbo, me sale un fallo de turbo p 226300, pero no se si realmente es el turbo o es la egr, me gustaria que me ayudarais, un saludo

    1. Hola Jesús,
      Ese código se refiere a una condición bajo o polainas. Esto podría ser debido a una fuga de presión en las mangueras de inducción turbo, (observar depósitos de petróleo negro en y alrededor de la manguera defectuosa) que se escapa intercooler, de nuevo, busque manchas de aceite. Si esto un modelo de pre 2006 comprobar el funcionamiento correcto de la válvula de accionamiento del turbo (debajo de la caja de aire – muy común fallan) o agujeros / fugas en vacío turbo diafragma del actuador. Si un modelo posterior en 2006 con doble turbo sospechoso se pegan brazos accionadores turbo o válvula EGR se pegue abierta.

      Espero que esto ayude.
      Todo lo mejor

      Hi Jesus,
      That code relates to an under or overboots condition. This could be due to either a pressure leak in the turbo induction hoses, (observe black oil deposits on and around faulty hose) Leaking Intercooler, again look for oil staining. If this a pre 2006 model check the correct function of the turbo boost actuation valve (under air box – very common fail) or holes/leaks in turbo vacuum actuator diaphragm. If a later model 2006 on with dual turbo suspect sticking turbo actuator arms or EGR valve sticking open.

      Hope this helps.
      All the best

  5. Hi Steve.

    Just had new bottom ball joints fitted so lots of thumping and banging involved, the van has come back to me with ABS, ESR (tyre symbol) and EDC warning lights on, assume all the hammering has ruined an ABS sensor?

    Is there any way of testing without a code read? (mechanic said his device would not connect, kept timing out) and can I assume that because my speedo still works the fault isn’t with front LHS (passenger) sensor?

    Thanks yet again


  6. Hi I have a 2010 316 Sprinter, with a Euro 5 engine. In the 3 years I’ve had it, its been great apart from the fact that on a run of 15 miles or more, if the ambient temperature goes above 18 degrees C the engine management light comes on and it goes into limp mode. I can switch the engine on and off twice to reset it but within 5 mins its back in limp mode . . . as soon as the ambient temp drops below 17 degrees on reset it performs as it should . . until the ambient temperature goes above 17 / 18 degrees. So in the UK for 9 months of the year its OK but in the summer and when in France it is in limp mode for much of the time. I’ve taken it to the local dealers for repeat diagnostics. They told me it was a very slight leak on the inlet manifold and that unless this was fixed it would remain a problem. It was ‘fixed’ with an acknowledgement that it might not have been leaking, and the problem continues, since then I’ve had the air mass sensor and inlet air temperature sensor replaced, as has been the EGR valve controller. I am now told that the boost pressure is outside its parameter because of a turbo waste gate malfunction, and I need a new turbo. Its been like this for 18 months. However whenever I point out that the the engine only goes into limp mode at 18 degrees or above I get blank looks and a response that they can only go on the diagnostics print out. In the last week there has been reference in the news that many euro 5 engines are designed to turn their exhaust emission control system off at 18 degrees . . coincidence or what. I has been suggested by the workshop staff that when its warm the air is thinner and this results in a change to the boost pressure . . I’ve pointed out that driving and 1000m in France the air is also thinner but if the ambient temp is less than 18 there’s no problem . . . and that is why the airmass sensor was changed. As far as I know the ambient air temperature sensor hasn’t been changed . . . because they say it only feeds into the dash temp gauge. Any ideas.

    1. Hi Mike,
      Well to be accurate to one degree of temperature whether the fault occurs or does not really rules out most things. Fuel temperature will not track ambient with such accuracy due to its volume, neither will intake air temperature because the temperature on the IAT will always read with a varying differential to ambient air as its located after the turbo and intercooler so will actually fluctuate more as a result of engine load and road speed than it will a one or two degree ramp in outside air temperature through-put.

      So what is it!

      If I wasn’t looking solely at the temperature issue for direction I would be saying, sticking EGR valve – that was perhaps commanded fully closed and still allowed some boost to disappear down the exhaust pipe. The fact that these items are a common achilles heel on the later NCV3 Sprinter and are very frequently found to give issue almost makes me first consider it and then wonder how the temperature could relate to it.

      2010 was probably in the catchment for twin turbo actuation issues that was later modified. If you were to purchase an over counter replacement from good old Benz, it would be of the later type. (though they would probably not tell you this) So I think your guy is thinking this could be the issue. My experience of failures (sticking actuators/internal vanes) has been temperature related but exhaust temperature – so this really discounts a couple of degrees of ambient.

      My final fling on the cheaper end of ‘parts darts’ would be the manifold pressure sensor (Boost sensor) not only because it remains unchanged in your parts list but it could have an issue where it is reporting a pressure at certain boost parameters (Air temp, Air Mass, Fuel temp, Load etc) that is out of the expected range or map predicted by the ECU for those conditions, resulting in a Limp condition. Resetting once the ignition is cycled.
      My advice to this problem would be change the MAP sensor, Clean or substitute the EGR valve for a known good unit and then and only then consider actuator or turbo issues.

      There is one further thing that could be ‘temperature’ related regarding the actuators, but would be a nonsense to consider if you had the electrical servo type turbo boost actuators. Some models do some don’t. If you do have vacuum controlled actuators, they are supplied by a common vac supply that also feeds the recirculation air and other climate control flaps within the cabin air vent circuit. Lets just muse for a moment that at a certain air temperature (18c) the AC or climate control (I am assuming fitted to your model) calls for an actuation of a flap in the ductwork to make the internal cabin air control more controllable in the selected range. If that pipe was broken or the actuator diaphragm was split not only would the flap not move to its required position but vacuum would escape, quite possibly starving the turbo actuators of the maximum required vacuum to fully open them, causing an under-boost resulting in a limp home. Though not your model (Earlier Sprinter) this could happen and is not an impossible scenario, so at least worth an investigation if not just a simple blocking off of any vac systems other than those used for the turbo control – just to prove it either way. You can read a little more of this on how it affected the older Sprinter here. In your case it won’t be exactly this valve, but could be one elsewhere in the circuit.

      Hope thats helped a little with your problem, its a good one!
      All the best

      1. Hi Steve. Thanks for your response. The EGR valve had already been replaced. On the suggestion of a local Merc mechanic we also replaced the fuel temp sensor. Mercedes has told us they think there must be an issue with them as they’ve sold 700 this year. We also tried turning the ac on and off but it had no impact. However all to no avail. We travelled through France in the warm and true to form it went into limp mode. Every now and then I would stop and reset it. Until on the day we were returning. On resetting it didn’t go into limp mode. It was 40 degrees. It worked ok all day until the evening when the air temperature dropped to 35. I’m beginning to think this might be a software problem. What do you reckon.

      2. Hi there Mike,
        Thanks for the update. I am smelling faulty air mass sensor. Further established by every other temperature sensitive device being changed. However there is one other that remains unchanged and that is the ambient air temp sensor that should poke through the lower grille somewhere. These get damaged by flying road debris. Although not immediatley and obviously connected, you would have thought the ECU may use this to establish engine running conditions based on outside temperatures??? Maybe, you are pushing my understanding of how things actually work here, but it does have an element of good sense about it.

        Back to the air mass device. This has a temperature bulb within it and looks at the change in resistance of another (it used to be a tungsten wire matrix) as air flows over it – The more air flows the cooler the wire or sensor becomes, changing its resistance. This Value is compared to the output from the shielded temp device and from the differential it can gauge the volume of air flowing through the fixed crossection or tube of the device.

        Change this next. It will need to be base-line set on Star, this calibrates its zero point. Just fitting one may give you more problems than you had before.!

        There it is…. No where else to go is there really? With fault occurrance at a ‘dead on’ temperature.

        Software fault…. Last resort hotel me thinks, as it runs fine other times. More likley an erroneous input device crapping the engine control unit out at a predetermined and frequently repeatable set of fault conditions every time.

        Its a difficult one, thats for sure!

        All the best

  7. Hi just wondering if you could help me. I have a 2000 Mercedes sprinter. I have like a boarding/humming sound sometimes and when the noise occurs it loses power, it drives as if the turbo not working, can’t overtake, ever hill at to go up in 3rd. Left van sitting for a few days, started it no sound and drove home strong. Baffled as this noise andpproblem comes and goes. People saying to spray egr cleaner into the turbo, scratching my head. Any advice would be great fully received as you were spot on the last time you told me about a turbo pipe. Many thanks’ jon

  8. Hi I have a 2002 sprinter 313 with similar problems. It goes into limp mode after a couple minutes driving. If I switch it off it won’t restart for a few minutes. Also I have an intermittent misfire that started today. It’s fine in neutral but while driving at low rpm it misfires. The only fault code stored was for a low boost pressure reading

    1. Hi joe,
      You may have an electrical issue with one connection to an injector, this could be as simple as a intermittent plug on the solenoid of the injector or possible a wire that is shorting to ground (the head) under the cable tray assembly. I doubt low boost pressure could be the cause of a misfire though if you have a non-EU, American or Canadian Sprinter it could likely have a sticking EGR valve, this would for certain cause boost pressure to escape down the exhaust and if it sticks open, even slightly it has an effect on low speed idle rather like a misfire. Its quite a simple thing to clean, take it off and treat it to some carb cleaner and a scrubbing, refit and see if anything changes. If so replace it with a known good unit at the earliest opportunity.
      Try the above in the reverse order, EGR first if you have one, then look for electrical issues.
      All the best

    2. I have a 2004 Sprinter and it went into LHM in Seattle. It cost me $600 to tow it back to BC. I took it to Eurotec and they diagnosed a frayed wire in the loom. Fixed it for under $300 so check your wiring.

  9. Hi Steve

    Replaced my old (2004) sprinter with a 2007 311CDI which is hinting at EGR problems (it smells odd, occasional belches of white smoke and a little down on power/fuel consumption a bit more than expected), no warning lights though and not in limp mode.

    I intend to pull the EGR for cleaning, it’s the device under the air filter, 4 torx bolts on a square flange? I’ve also been advised to check/clean the turbo boost sensor at the same time but can’t find it, where in the pipework would I find it?

    One final question, what does the red knob on the air filter box do?



    1. Hi Max,
      Sensor is in the exit from the intercooler to manifold run, the temp sensor is actually in the pipe and visible if you get underneath and look at the pipework from the right hand side (if under front) The red knob is your battery jump point as the battery is under the floor inaccessible, moving the red plunger reveals a jump lead contact portion. It sounds pretty much certain its the EGR thats on its way out, you may get lucky and manage a successful clean up where you describe but often it returns.
      All the best

      1. I pulled the egr and it wasn’t particularly dirty, 2 minutes with a toothbrush and some carb cleaner and it’s sparkling, the propeller shaped rotor turns freely and snaps back closed.

        No improvement in hot idling, it’s makes an uneven churning noise, is this an indication of being stuck open or closed?

        Time for a code read? Still no warning lights on the dash (yes all the bulbs are there).



      2. Hi Max,
        OK on the EGR valve, as you say best get a read and see what it turns up, as of now we are both guessing!
        All the best

      3. Code read today Steve, no faults but………

        The mechanic used the laptop to force the idle control valve closed, this immediately smoothed out the idle and stopped the smoking/smell, unfortunately as soon as he unplugged the churning rough idle returned.

        So, I need to find the idle control valve, is it something that can get gunged up and partially stick or is it time for replacement? I’ve got my toothbrush and carb cleaner ready, just need to know where to find the valve.

        Thanks again.


  10. My 07 Sprinter/Mercedes limped home. I was sure it was a plugged air filter because I had no power. Upon taking apart my air filter box assembly I noticed that one part of this assembly had a lot more play in it than I thought was normal. Almost hidden from view I finally noticed that this “loose” part had detached itself from the Turbo entry point and this was the cause of the no power. It took me a total of 3 hours to fix and no parts required This saved me.about $400 to 500. including a tow. Lessons learned = Look closely at everything . If it looks unusually flexible investigate, check your connection, both electrical and mechanical. Ask others what to look for. Maybe you should sleep on it “patience” is your best friend and helper.

  11. Hi
    I’ve got a 313 2003 sprinter in limp mode, I’ve read a lot of postings and carried out repairs to what people are saying is the problem but still no joy.can anyone help. The actuator on the turbo doesn’t move when revving, I’ve renewed the boost actuator and rewired it but still no joy. If I suck the pipe to the turbo actuator the lever moves down with no trouble. I’ve tried the new boost actuator on another sprinter and it works fine.

    1. Hi Tom,
      If you have tried the simple things its time to get serious and get a code read that will give you some idea of whats going wrong. It may not tell you exactly the component that is faulty but it will help you find valuable pointers to the root cause. So often parts darts becomes costly and as you have discovered, at the very least irritating! It could be any one of a vast amount of things that are holding off the turbo and applying limp mode, and to try and find it without the aid of electronic diagnostics would be quite a task. The best advice I could give at this stage would be to go and get a comprehensive code read, and see what it turns up. Either do this at dealer level, expect £45-£60 or at a good independent with access to a STAR compatible reader £25-£35.
      Once you have the codes you can begin to systematically eliminate things and get yourself on track and ultimatley sorted.

      Hope that helps, when you have them, share the stored codes and we can take it from there.

      All the best

  12. Hi Steve
    Thanks for your prompt reply. I have had a diagnostic done by a “sprinter specialist ” who used a snap on reader and got the code P1470. But he is unable to make any sense of why it’s not working. So I’m left at a lose. Maybe I need to just take it to MB.

    1. Hi Tom,
      Well you will have probably realised the 1470 code is a generic code relating to boost pressure. With a specialist reader it will give one of a number of sub codes. It could relate to short/open circuit in the boost control valve wiring, turbo boost overpressure, turbo boost under pressure etc etc. It could even signify a faulty boost pressure sensor which is in the hard plastic coupler section from the intercooler to the inlet manifold. (the inlet temp sensor is next to it too) I would pull this sensor out and check the hole in the end is not blocked with oil and crud. Spray it with a little electrical spray or MAF spray to clean. Better still replace it. If that does not work, in light of the other work you have done in this area I would have to concede awaiting a more accurate breakdown on the fault code. Perhaps try a Mercedes independent car garage, the OEM style diagnostic equipment they have will also work on sprinters and are likely to have a proper STAR compatible tool which will give you the accurate sub code you need. Try Mertec in Kent, they should have STAR kit that can read your codes, see if they can do it for you.
      Mertec (Kent) Ltd
      (also known as Mertech)
      Unit 4 Oast Park, Spade Lane
      Hartlip, Kent ME9 7TT
      ME4 5AY

      Just one other thing, the cabin ventilation air box under the bonnet has a block off flap that comes into play when you press the recirc button inside the cab. Is this working correctly? If not you may have a vac problem, or at least a reduced vacuum. See here what sometimes can happen.

      Hope that helps,
      All the best

  13. Hi Steve
    It was that “just one other thing” just been out and checked and you was right the pipe the the heater was off, pushed it back on and all working now. So much for the sprinter specialist with 30 yrs expiriance.
    Thank you so much for your help.

    1. Hi Tom,
      So pleased you found that! What happens it the disconnection to the flap actuator starves full vacuum from the system causing the turbo actuator never to make full retraction, this in turn trips the ECU into limp because of an underboost condition. As soon as full vacuum is restored the correct boost range is obtained. The ECU would never have held a fault code for the vacuum leak as its a physical mechanical thing and it can only report on controlled systems – this it just assumes exists! Anyway sorted and I am very happy for you. Thanks for the donation by the way, not many people do that by means of a thank you, and it is appreciated. You are now a member of the ‘Elite’ Gen In user club !

      All the best, keep in touch.

  14. Hi, I have a 2011 313 cdi. Goes into limp mode when it feels like it. Rear loaded or unloaded.
    Usely on the motorway and around 65mph. Delphi comes up with boost pressure incorrect flow -intermitenet.
    Any ideas? a freind with a 2015 had same issues and his was the boost transducer, not sure if its the same engine or not but is this worth a try ?
    I have changed the inercooler pipe as the fan cowling had come lose and 90% rubbed through it. Origanlly thought it was this but it hadnt 100% gone through

    1. Hi Dave,
      There is known issues with the twin turbo actuator set up on this age of vehicle. Usually it is heat related, centred around sticking actuators / rods. (Some are vacuum controlled some are electronic) It may be worth a quick investigation to see if everything is free to move through its full range and give it a generous spray with some penetrant/lubricant and seek some improvement. There is also a chance it could be the EGR valve sticking slightly open, sapping off turbo boost pressure directly down the exhaust, this again is a popular failure point on this Model Year and well worthy of investigation.
      Hope this helps,
      All the best

      1. Sorry I’m replying to a post but actually have a new post. My 2006 Sprinter was idling in my driveway prior to take off yesterday and I noticed a trail of oil like fluid rolling down my driveway. It seemed to be coming from the left side of engine. I towed it to shop and they said my fuel injector pump was leaking badly from the bottom. Diesel fuel was just. Gushing out. Has this happened to others? The engine still ran no check engine lights came on just diesel fuel everywhere. Part of my serpentine drive belt was also eaten away by the fuel spill. Any comments?

      2. Hi there,
        It is not unusual for the HP pump to fail in this way, it is in fact a small O ring that fails on one of the three heads.
        All the best

      3. I have 440,000kms on this engine and have never had an issue with the fuel pump. Mechanic said it needs a new one so I went and got one for $1100 a Bosch reman. But when he took it off he saw it was just an owing like you said and he ordered it and put it together quickly. His bill was not bad but they charged me $100 restocking charge for the pump.

      4. Great news Stojan,
        It saves a few dollars in the end, quite often you can a buy a second pump cheaply from Ebay and refurbish it ready to fit for the future.
        Best regards

  15. Hi Steve
    Can you tell should my sprinter rev past 3000 without putting the clutch down? It’s all drive ing OK turbo boost kicking in and going above 3000 revvs when drive but turn it off and restart and it only revs to 3000
    Thanks Tom Eldridge

    1. Hi Tom,
      Perfectly normal. If it wont rev past 3k after a clutch actuation at start up you most probably have a limp home issue, but initially from start up the 3k limit is imposed by the ecu before any controls are touched.
      All the best

  16. hi i have a 1996 312d 2.9 sprinter camper van with 57.000 on the clock the problem i am getting has you slow down for a junction it seems to loose the throttle then clouds of smoke pour out of the exhausts and a strong smell of diesel i put some fuel system clener in the tank and took it for a sixty mile run it runs fine at 70 mph but still when you take your foot off the throttle it still does this its ok if you keep a little rpm has you come to a junction a mercedes van dealer first said it was injector problem then said it was high pressure fuel pump and was talking £1500 to change it so at the moment i have told them not to change it no confidence in the dealer would you have any idea where to look next regards pete

    1. Hi Peter,
      Check on the rear of the mechanical fuel pump there are vacuum hoses and a mechanism, if either is faulty, leaking or seized then there will be no pump advance retard control and fuel regulation vs engine load will be lost – re overfilling on overrun. Could be a simple fix. Give it a good looking over and make sure nothing is split or rusted up.
      All the best

  17. My sprinter 311cdi 2002 has limited power. Not full limp mode. If you rev it it stays at 3500rpm, turn key on and off and rev to 4000rpm, this I know as full power mode as everything spools up and drive flat out. Take foot off throttle and apply again and half power Again. I have changed EVERY sensor, actuator, regulator, high pressure pump, two injectors because they were leaking off badly, gone through all the wiring, cleaned all grounds, full ecu pin out to everything, changed ALL fuel lines, filter, everything, I’ve done everything and I’m at my wits end. Only code I have is p1188 element control valve general error, I’ve tested everything on this valve, it’s now brand new and further tested…..please help.

    1. Hi Richard,
      Well this is a teaser. That code is specific only to the pump mounted solenoid valve – that turns off the third element of the mechanical fuel pump. It does this when commanded to reduce pumped fuel pressure, actioned by measured excessive rail pressure, its a safety device.
      As its a ‘general’ error its impossible to determine what the issue is from the generic code, short, open circuit etc etc. So a more definite drill down of a code read is required to assist you, probably from a STAR reader or compatible that will hopefully give away a little more detail. I suppose you tested from the valve plug to the ECU as the loom is often holds a few surprises as it loops over the right hand engine mount (looking in) and then onward to the bulkhead.
      Hope this helps,
      All the best

  18. Hi,
    I have a 2003 Sprinter 313 cdi that does not rev up above 3500 rpm, the lever in the turbo is not moving when the engine is running/accelerating. I have measured the 12v supply line to the Boost Pressure solenoid harness and it is actually 12V (referenced to ground), with the other line(the control line) is not doing the PWM, is fixed in 3.5V, and is not changing when accelerating either. What do you think about this situation? Thanks in advance.

    1. Hi Edgar,
      The van is in limp mode, all turbo control is halted to protect the engine. While it is in this mode you will not see any PWM or movement of the lever on the turbo body. If you have an EDC lamp lit on the dash then this would need to cleared to see at what point the the fault occurred, and it illuminated. A code read would the best bet with a compatible reader that gave a little more indication of where the fault/problem lies.
      Hope that helps
      All the best

      1. Thank you very much Steve, there isn’t an EDC lamp lit on the dash, so if there is not EDC lamp lit, it is possible to read any fault with the compatible reader? Thank you.

      2. Hi Edgar,
        Yes indeed, there are a set of what are called ‘pending codes’ sort of a list of fault codes that occur ‘infrequently’ or deemed minor, and would generally reset by a start cycle. These can be read with a compatible code reader and are a great aid to pinpointing troublesome issues.
        All the best

  19. We recently “tried” to have our sprinter 312d remapped. After the remapping process the ECU was plugged back in, started the engine and within 5 minutes it cut out. The EDC light was flickered 2 – 3 times before the engine cut out. Now the EDC Light & Glow plug light stays on and it does not start at all. We are getting someone with the appropriate code reader to see if any fault codes are stored.

    Meanwhile any thoughts on what could have happened, what to check, and how to get the engine going would be greatly appreciated.


    1. Hi John,
      There are a group of brown ground wires above the negative battery post, these often corrode to the chassis earth. Clean them up and look for other tell tale signs of poor grounding. The plug and sockets on the ECU are very picky about any tarnish or corrosion that may be present have a check that everything is clean and bright as often water finds its way either from the screen seal or through the bulkhead bung onto the ECU connectors. Chances are if nothing else has been disturbed the problem either lies with the loom connection under the dash to the ECU or even a bad flash (remap)
      Hope that helps

      1. Hi Steve,

        Thanks for the advice – will check and report asap. I had a diagnostic code read yesterday and no DTC’s were found. The guy who did the remap swapped the ECU from a W202 C250TD just to check things out – the EDC light goes off but the glow plug light stays on. It has been suggested to me that I should buy a Glow Plug Relay to rule that out.

        For what it’s worth my gut instinct tells me that it is either a case of remapping gone wrong ( which could be verified by plugging in a identical non-remapped ECU ) or something in the electrical department.

        Never had a problem with engine starting and / or cutting out in all the time of our ownership. So, if it fails to start and / or cuts out immediately after a remap either it’s a case of extreme coincidence where other things ( bad earth , glow plug relay) have decided to go awol at the same time or remap is incompatible with the ECU hence the engine cutting out. I also remembering hearing some strange engine “knocks” before it cut out.

        Do these old Sprinters have immobilizer or something in the ECU and could the remapping changed something with that ?

        Many Thanks

  20. Hi Steve,

    Removed the group of wires by the negative terminal, cleaned them, sprayed contact cleaner and put them back. Also the contacts the ECU looks ok – removed the plug connector and sprayed some contact cleaner to clear any condensation / moisture etc. This.however, did not clear the EDC and Glow plug lights though.

    What I cannot understand is immediately after the remapping guy plugged in the ECU it started the first time but cut out within 5 minutes – there were some odd noises / knocks + EDC light flickering before it cut out. It started again the second time but cut out again in 2 minutes. It never started after those 2 times.

    I am guessing that the engine’s ECU has a problem with dealing with remap files and cuts out. As there are no diagnostic codes to read I am totally confused as to how to proceed with getting the van back on the road.

    Anything else I could try before forking out for a new ECU and / or any other clues on how to tackle this no start issue would be greatly appreciated.


  21. Hi
    I have a 1999 311 sprinter, keeps going into limp mode, gets up to 40mph then nothing, it has also started to give a exhaust smell coming into the cockpit vents, I’ve cleaned most of pipes going to the turbo and cleaned the sensors . Also taken it to have a diagnostics check shows no faults!! Any advise please
    Thanks Shaun Abbott

    1. Hi Shaun,
      Have you removed the black plastic cover from the rocker that reveals the injectors? This would be my suggestion to see if you had any injector seals that were leaking. To remove this you will have to remove the top half of composite the inlet manifold.
      Hope this helps,
      All the best

  22. i have a 2007 freightliner sprinter. often, it will go into limp mode but i can turn the key off then restart and it works fine… in 3 months it worked this way… maybe once a day, sometimes more…then it would not release, had the codes read at auto zone then cleared and it was released and worked fine for a week… then locked again and took to dealer shop. where i was tild it could be many things but if he fixed these 3 items, 12,000.00 dollars worth it would be fine. But still not telling me the cause of limp… what your saying is it could be a vac hose or 1 of these sensors…turbo… HELP

    1. Hi Larry,
      Indeed it could a lot of things from a simple hose to a failing turbo! I would recommend that you try and find a good independent shop that has a Snap-on Solus code reader with the correct module for Sprinter and pay them for a full diagnostic session. This should be able to pinpoint the area of the problem reasonably accurately and rule out, prove or disprove what the issue could be. It would at least be good to have a second unbiased opinion and work forward from there.
      A lot of the fault finding on the older Sprinter T1N >2006 was a little more simple than the later twin turbo set up on the NCV3 Chassis 2.1 4cyl. and although the principals are the same the later system is a little more complex.

      Hope that helps you a little Larry,
      All the best

  23. Hi Does the ECM ECU – 2010-2013 Mercedes Benz Sprinter Engine Control Module ECM ECU 45K OEM LKQ have a memorie can you get info of it

    1. Hi David,
      If I understand your question correctly the ECU of all MB vehicles can store and retain codes relating to engine faults. This can be read with an appropriate dedicated OBDII reader such as Mercedes Styar or its near compatibles.
      Hope this answers your question,
      All the best

  24. Hi Steve

    I have a 2011 2.1 vito that goes into limp mode.

    Using an OBDII reader it comes up the generic code P2454-DPF Differential pressure circuit low.

    Any ideas what it could be please? I have looked for the egr to give that a clean but can’t find it. I previously had a 2007 vito 2.1 and the egr was easy to find on the left rear corner of the engine if your stood looking into the engine bay from the front. Have they moved it?



    1. Hi Paul,
      There is a lot of rubber pipework connecting the DPF differential pressure switch to the DPF unit, check that everything is in place there. There is a chance the pressure switch is faulty and I suggest swapping that before going on. As I remember its a £20 part and could mislead you into thinking the problem lay elsewhere if faulty. The RWD W639 Vito 2.1 has its EGR on the rear right as looking in, Connected to some rigid alloy casting and box cooler – just along side the back edge of the fuse/control box – I bet you wrote that from the drivers seat 🙂
      Once the pressure switch is known good and the connected pipework sound then perhaps invest in a good code read with Star or dealer compatible tool, this will be able to give a range of sub codes to further pinpoint the problem. Its a good investment, especially as DPF problems could be wallet bending if you got it wrong and replaced the wrong part!

      All the best

  25. Hi Steve

    Thanks for your quick reply. I was stood in front of the van and meant right hand side not left!!! So it is in the same place but connected to the alloy casting too now. Looks a nightmare to get to to remove?

    Since sending you my questions I removed the pressure switch and gave it a blast of carb cleaner then compressed air in the ‘pipes’ and also contact cleaner on the pins and plug. Also blasted the pipes with air that connect it to the DPF. The fault code has now cleared.

    Hopefully that’s all that it needed. I still would like to remove the EGR to give it a clean as I know these can cause DPF problems. Do you know much about Terraclean as this is supposed to clean out the EGR. I’ve read mixed reviews about it.

    Can you recommend a good code reader that’s affordable please?

    Thanks again


    1. Hi Paul,
      Don’t know much about Terraclean, it sounds like one of those wonder products that repairs head gaskets without lifting a spanner! The best code reader to have to hand would be the Autel Maxidiag MD702 which will do European cars and Sprinter. If you did have a few quid extra to spend get the one that does all models MD802, Jap etc as this is truly a universal tool and you can earn its cost back pretty quickly reading ‘mates’ cars etc.

      Hope that helps
      All the best

      1. Hi Steve

        Got the van fixed. It was a faulty DPF sensor. Also got the Autel tool which did help massively sorting out the possible causes.

        Thanks for your advice


  26. Hi guys. I have a 02 sprinter that goes into limp home mode after a few minutes driving. Once it goes into limp mode if I switch off the ignition the engine will not start again. If I leave it a while and come back to it then the van will start first turn of the key. The 4 injectors have been replaced and leak off test carried out on all. Fuel pressure regulator & boost control solenoid have seen replaced. Intercooler and hoses are fine. 1 fault code for underboost but once deleted it doesn’t return & a fault for glow plugs cylinder 1&2 that has been in the van with years. Live data shows 250bar fuel pressure when cranking & at idle, 2200bar at full boost and fuel pressure does not drop when it won’t start. Boost pressure showing 2.2 bar before limp mode and 1 bar when in limp mode. Any idea where to go next? I also have a fault code for crank/camshaft synchronisation but reading up that seems to be a generic fault caused by cranking when it won’t start. Please help!!

    1. Hi Joe,
      Any synchronisation error code is likely to be accurate. Often the camshaft sensor due to its position will fail in a manner that reflects a warm or cold engine fault condition. It gets subject to heat in the extreme and many heat cool cycles, for the cost involved that would be my first port of call. Change it to be sure. You can also test the crank sensor by watering it down (right hand side looking in, above the starter) when the engine does not start to cool it off, if it then starts suspect the sensor.

      If none of the above – The fault you have there sounds very similar to the pressure regulator solenoid on the back of the fuel rail being faulty in some way. I know you said you had this replaced but wonder if the replacement was new or used part? The tiny green O ring is generally the only item to be faulty here, either nicked or worn allowing some pressure bypass.

      The low boost flag I think is a red herring as it slips into limp mode, and as you say, these engines are capable of starting/running without issue with no functioning glow plugs!

      Hope this helps in some way
      All the best

      1. Thanks Steve,
        The fuel pressure regulator was a brand new unit with new seals.
        I will replace the cam sensor and will try cooling the crank sensor if the problem persists. Hopefully this will sort it. Thanks again

      2. Hi Steve I tried what you said there with cooling the sensors and it made no difference. Strangely enough tho if I pour cold water on the turbo it seems to start almost straight away. Is that just a coincidence?

      3. Hi Joe,
        I cant see the turbo preventing starting to be honest. I would still dubiously suspect the cam sensor on the back of the valve gear cover, especially now you have had no luck cooling the crank sensor using a real ‘shade-tree’ method.
        All the best

      4. You were spot on Steve. Replaced cam sensor no more limp mode, no more non start!! Thanks a million

  27. You have given the best answer on any forum ive been looking on. I myself have been a mercedes machanic , technition what ever we are classed these days for the last 25 years and some of the replies i have read regarding power issues. And what and what not needs changing well i not sure where they are getting it all from. Any way well done a spot on diagnosis. Great read. Andy

  28. Hi Steve

    I have a 2011 313 sprinter, I’ve just replaced my older model.this one has 180k on it but full history,drives fine but …..
    When starting it turns over 3-4 times before starting ? May be nothing but my older one cracks up straight away.
    When I drive and it seems to be more when higher speed motorway ( although not always). The orange engine light flashes and it goes into limp home mode. If I turn it on and off 3 times then the light goes off and all is fine ??

    Help lol



    1. Hi Adi,
      It could be as simple as the fuel filter requires replacement (use genuine MB one as pattern parts sometimes do not use the correct flow rate filter material inside) The laboured starting may be related to a slight air leak in the fuel supply system, whereby its draining back to tank over time, suspect this if warm starting or re-start after a short period of rest is good and more rapid then when it has been standing for several hours.
      Best thing you could do if once the fuel filter has been replaced, and there has been no change, is to go and get a good code read using a STAR or compatible reader. This should give you a more accurate idea of where the fault could lie – without this as a guide its just finding a way in the dark and parts that are not needed can become costly!

      Hope that helps,
      All the best

  29. Hi Steve,

    I have a problem with a 2000 5cly diesel Mercedes sprinter –
    when driving it home , while at the traffic lights the engine just started to bounce around creating a banging sound within the cab.
    Coming from the exhaust was huge amounts of black smoke.

    I’ve since cleaned the EGR valve and its connecting body – still no change.
    I tried moving the turbo actuator and it was way too firm.
    so i unbolted it from the mounting position and was able to freely move the lever in and out.
    while doing this oil pumped out of the actuators air line pipe .
    its therefore filling the actuator with oil –
    what does this seem to be – a faulty actuator or turbo?
    Ive checked the external visible vanes and they are very good.
    the shaft has approximately 1mm play up down and back and forth.
    Im afraid to change the actuator incase i pump more oil into it. – Im guesing if the current actuator has been filled with oil the diapghram has probably collapsed?

    best Regards

    1. Hi Paul,
      There is a chance the turbo seals are leaking, what oil content is there in the rest of the induction homework, from the intercooler to inlet manifold? there should be a little not a lot. As I remember the 2001 model has no electronic turbo boost actuator and all the control of the turbo is done through pipework on the turbo / inlet housing. Please confirm if this is the case. What happens if you apply a vacuum onto the actuator does it move its full stroke?
      If the internal diaphragm is not damaged you should be able to clean out the oil by using a degreaser and pumping the rod until clear.
      I think there is maybe an issue here, but would see while oil smoke not black. Black is a signal of poor combustion and overfuelling. I would investigate the possibility of a faulty injector, perform a leak down test on each and be sure. While the turbo may be faulty /have problems, it should not effect idle and this is why I think there may be an issue with one or more of the injectors.

      Hope this helps a little
      All the best

  30. Hi

    I have a 2007 year Mercedes Vito that has the exact problems you discuss above. The vito runs fine while moving and on first starting, however, once clogged in traffic, the limp mode comes in sometime with EML on and sometime not.

    My garage has replaced four sensors to date as they were showing faulty when EML did cone on, thus problems too when I switch ignition off and re-start again, but reverts back once stuck in traffic again !!! Ughhh !!!

    Any idea ??

    1. Hi Allan,
      Some Vito W639s around that era had a modified EGR valve on a Mercedes recall, ring a dealer, give them your VIN and ask if its been done at some point in the life of the van. I would suspect probably not. If the issue is at idle its highly probably the EGR valve is sticking open slightly causing limp home. That would be my first point of call.
      While on the phone enquire if the safety recall has been done to the spare wheel carrier assembly (if you have underslung rear spare wheel) This carrier assembly could fail under metal fatigue and as a result drops the whole spare wheel onto the carriageway – not nice for those behind.
      Hope that helps
      All the best

      1. Hi Steve

        The problem is periodic, sometimes the an runs fine for days at a time. Then without warning whilst the engine is in tick over mode or whilst idling, on acceleration the turbo does not kick in.

        Also, the light warning of a carbon build up came on, but a half hour blast up an A road cleared this. The problem has now got that every time I stop st lights or I. Traffic it happens. A quick turn off of ignition and it is fine again.

        Is it worth replacing both the EGR valve and the electronic actuator ???

        Your advice is invaluable thanks


      2. Steve

        It’s me again!!

        Have spoken to dealership and there are no outstanding recalls due for my vito.

        I refer to my question above, many thanks


      3. Hi Allan,
        I would still remove the EGR (and give it a clean with a stiff brush and carb cleaner), clear out its seat and as much accessible pipework as you can get to. I still think that this is the most probable cause and without a code read to pinpoint it further I would focus on that The EGR only operates at idle and low rpms – just the circumstance you experience the issues with limp home and EML. Good to know the recalls have all been done. Do you have a DPF on that model? I had a 2008 that did not have one fitted from standard factory build, is this what you mean by ‘carbon build up light’ and the system performed a regen when you took it for a blast? There is a lot of tubes and thin bore pipework connecting the DPF if fitted to a pressure switch. These sometimes get blocked with soot, require a blow with compressed air to clear or in some cases a faulty pressure DPF pressure switch can give rise to reported back pressure issues that may result in limp home – however my own thought is that things would be worse as speed and not idle, pointing once more to EGR related issues. When idling does the engine become lumpy or change its note when the fault happens and EML light illuminates? – if so doubly convinced its EGR related
        Hope that helps.
        All the best

      4. Hi Steve

        Has the EGR Valve completely cleaned, problem is still evident.

        Engine management light comes on and goes off at will and now the air filter light has come on.

        Do you think it could be the air mass sensor that is faulty ???

        Let me know please



      5. Hi Allan,
        Not too sure what you refer to as the air filter light? Perhaps explain what you are seeing and I will try and identify it. The MAF sensor could be faulty though the garage would have seen this code for sure. Cleaning it is pretty simple with some MAF spray or Electrical contact cleaner (called ‘Spark’ from GSF), from GSF or other auto parts outlet. I think now is the time to pay for a good code read on a Mercedes STAR or compatible reader and look at the print out. It may cost you £45 or £50 to get this done, but it will hopefully save all the messing about changing parts unnecessarily. By all means try cleaning the MAF element with the spray mentioned, let it dry thoroughly before reassembly and give it a go. If this fails then really the best bet is to get a good code read that can narrow the field and drill down more accurately than the one used currently by your garage.
        Hope this helps.
        All the best

  31. Hi there, i have a 2011, 313 Sprinter. 156,000 on the clock with full MB history.It runs great except on tickover, it won’t tickover. The revs surge up to 10,000 then drop to 8,000 it does this several times then cuts out. Initially it only happened for the first 5/6 miles eg if stopped in traffic or at lights. Now it happens all the time it even cuts out when slowing down and engine management light will start to flash. If i stop and remove ignition key, wait a couple of minutes for all dash lights to go out i can restart and no management light on. Still no tick over though. It had full service 2000 miles ago everything changed. Any suggestions gratefully received. Thanks, Maggie.

    1. Hi Maggie
      The most common fault relating to surge and stall at idle is air in the fuel delivery system, usually between the low and high pressure pumps. There are hard clear plastic delivery pipes you can see on the front of the engine, any bubbles or froth in these will be for sure related to your issues. There are O ring seals on these lines that can be replaced for only a few pence that usually cure the problem. Worst case would be a faulty fuel pump, most probably the low pressure pump. Inspect the delivery pipes for air and if it exists have the pipe seals replaced.
      All the best

  32. Hello I wonder if you can help me I really am at my wits end I have a 2011 plate Mercedes Sprinter 316 twin turbo the vehicle has 175 thousand miles on the clock which I would not believed to be excessive I’ve taken my vehicle to Mercedes-Benz several times but with no joy I have spent lots of money on this vehicle with mercedes changing lots of parts but the problem seems to still come back, the problem being a flashing ECU light no fault codes present, the vehicle goes into limp mode but you turn the engine off and turn it back on twice the problem goes away but then after a certain amount of miles normally on the motorway in cruise control at 60 miles per hour the flashing ECU light comes back again, mercedes have told me they think it could be the turbo worn but not 100% sure they say it is a boost problem, they are also telling me that there is a rattling coming from a timing chain area and that the that the timing chain could be stretched, they have advised that I need a replacement engine and maybe a new turbo, from them costing over £5,000 something which I just simply cannot afford I’ve noticed that this problem does not occur if I drive the vehicle at 70 mile an hour in 4th Gear as soon as I put it into 5th gear and the revs drop down this is when the problem occurs when I’m trying to get the optimum fuel consumption. the problem being a flashing ECU light, someone at mercedes Benz told me it could be the DPF filter one other technician said it could be a faulty ECU with a dry solder joint lots of people have suggested lots of things but nobody seems to know can you help me? Do you know of this fault has anybody else experienced this fault and received the same service that I received yours faithfully Michael

    1. Hi Michael,
      The flashing engine managent lamp is a bad sign for sure. Any timing signal confusion from the cam or crank sensors may cause issues similar to this although not to log any code is strange. If it were me and for what relative cost was involved, I would change the crank and cam sensors, if for nothing more than piece of mind or simply to rule them out of the equation.
      There are only a number of things that can play up and not register a code, however for the trained mercedes man with STAR diagnostics at his disposal he should be able to look deeper into the ‘event log’ and see exactly what is going on, so the ‘nothing showing’ comment is somewhat weird. Maybe take it to another dealer for a full diagnostic session, explain that the event log may hold the key to the issue ans see what they say.

      To go back to the timing issue, do you hear any clutch noise, does it judder or rattle badly on idle. Other than it has has been reported that partial break up of the dual mass flywheel can in part, due to vibration, mess with the reporting of the crank timing signal as the pick up teeth are on the flywheel itself. Just a thought.

      My own view is its unlikely to be anything to do with timing chain stretch, its a duplex chain and very strong indeed. I maintain vehicles with 300k miles on the clock that are abused every day and I have not seen an issue related to chain stretch ever.

      Hope that helps, its a difficult one, thats for sure.
      All the best Steve

      1. Thanks Steve, I think I wil get those sensors changed,I dont accept that it needs a new engine as it drives and idles lovely, no rattle and it had a new clutch last year, do you think that the turbo could cause this as ive noticed it surging in first and second gear as I pull off, M B dis say its showing a boost problem.
        Kind regards Michael

      2. Hi Michael,
        The turbo could be faulty, mechanically inside, stocking vanes. However surging at take off is really only usually attributed to poor or variable fuel pressure at the rail. That is if your description is what I call surging.
        Did the problems start after the clutch swap, if so and you had the dual mass fw replaced this could have damaged the crank sensor during replacement.
        See what happens with new sensors first.

  33. Hi steve ,ive got a 311 07 plate that is slow up hills will not rev above 3200, engine light is on, strong smell of fumes when windows open, sometimes on start up runs ok but then will not pull again, white smoke when start up then clears, any help would be appreciated thanks rob.

    1. Hi Rob,
      Pull the breather hose from the PCV oil separator and check for blow by fumes, if this is good and there is not too much visible fuming there is a chance the turbo seals could be allowing some oil to pass, this is passing through the inlet tract and being burned with the combustion mix. Are you using a lot of oil?
      All the best

      1. Hi steve thanks for the reply, not sure were the pcv oil separtor is, also not using alot of oil, and the fumes i mentioned are more fuel than oil smell, reading some of the problems with mercedes, i not sure if its dpf thats choked up or s something else, map sensor maf sensor, air temp sensor, the turbo seams ok as it runs pretty good sometimes and on this model they have a electronic actuator not like the earlier mercs so i dont think its a problem there, hope this helps a bit more, many thanks, its a shame mercedes aren’t as helpful when you phone them, kindness costs nothing, thats there problem.

      2. Hi Rob,
        On top of the rocker cover is a black oil separator with a hose that exits from here and enters into the pipework before the turbo, pull this off the separator and see if you have excessive fuming. If you have, this could be caused by as you say a blocked exhaust but more likely is a worn engine/bores or damage/wear to piston rings. You can get a code read from a good independent with a suitable MB diagnostic tool, they will be able to look at live data and view back pressure in the exhaust. This would tell you if your DPF theory was correct at least before spending any more.
        Hope that helps

  34. Hi Steve,

    2002 313cdi less than 30,000 miles.

    A while back I had the van go in to limp mode, couldn’t get it out. Replaced vacuum control valve and boost pressure sensor. All good.

    One frosty morning found it was in limp mode, but 15-20 minutes later and after stopping at a shop, re-started, no limp mode. I put that down to ice in the pipework.

    The other day raced up a two lane hill in outside lane, luckily at the top it went in to limp mode. I could not get it out of limp mode (perhaps, or more likely not using correct procedure). After faffing around on the side of the road, I ended up blocking off the vacuum intake under the bulkhead. That gave me boost, a little too much, so kept speed down. After about 20 miles filled up with diesel and removed the temporary block and all seemed okay again.

    I forgot to say… As this is the second time this has happened and the faffing around on the road side, I’m going to relocate the vacuum control valve (vcv) on top of the headlight/air filter box and fit a manual flow control valve between the vcv and inlet under the bulkhead.

    I’ve just remembered… I had another incident where I had been motoring on for an hour or so, then it went in to limp mode. Stopped for a cup of tea and read through the fault codes, nothing. Started up and all was fine again. Very strange.
    Any thoughts please and what is the correct procedure for resetting via the ignition key?



    1. Hi Steve,
      Sounds like a possible vac loss, be interested to know if there was any correlation with the operation of the heater air recirc flap as this works from the same vac supply. Its teed off from the spigot on the servo supply hose and goes to an actuator valve via hard brown pipe. Any leak here results in reduced vac supply to the turbo VCV and underboost tripping. Have a look here –


      1. Don’t suppose you know what the working vacuum pressure is (if you can call it pressure when its a vacuum)? Just thinking I could fit a vacuum gauge.

      2. Hi Steve,
        I presume vacuum on the vac pump circuit that supplies the servo as the engine of course runs in a positive forced air pressure scenario. I am unsure of what value this would be to be honest and don’t have the figures to quote. If you disconnect the upper brown hard plastic pipe from the Y connector on the face of the brake servo (this goes to heater recirc flap) you could attach a gauge and see what you get and choose your range from this real time reading.
        Hope this helps

  35. Help please
    I’ve a 2011 sprinter 313 cdi
    It went into limp mode .took it to garage they said itshe the boost pressure sensor so the replaced it . Still fault
    Changed inlet pressure sensor today
    Pulled away from garage with 500 yards em light flashing again
    Any advice

  36. A few days ago out of the blue all kinds of warning lights came on in my 2011 MB Sprinter. First the tire pressure light came on but the tire pressure is fine. Then the ABS and ESP warning lights came on. Then the yellow engine symbol and the skid symbol came on. I went for a short drive to see if that would clear the tire pressure light but the vans automatic transmission would not shift out of 1st or 2nd gear. At anything past 35 mph the RPMs would race.
    What is going on?

    1. Hi Dave,
      Chances are you have a poor ground or battery supply cable. It is common for the battery Y cable that runs from the battery to the starter to corrode in a manner hidden from the eye. It splits off in a Y type crimp to the main fuse board. Any problem here and all manner of faults appear because of low or intermittent voltage caused by a poor or failing connection.
      Hope this helps

  37. Hi Steve,

    I have a 2016 4×4 Sprinter with 13,000 miles on it. My check engine light comes on and we get a P154800 error code – intake air temp too high. My Scangauge reads IA temp of 128*F at 65 mph on the freeway with OAT of 70*F. MBZ initially diagnosed a plugged air filter and changed it, no improvement. Took it back and they have had it for a total of 5 days now, still not fixed. I think they changed the sensor, but I’m not certain of that. Can you tell me what the difference in IA temp and OAT should be at freeway speeds/ Other sources online say 10-20*, but I’m not sure if that is C or F. MBZ tech doesn’t seem to have a concrete answer to that question. Thanks,


    1. Hi Ray,
      Simple checks first is the matrix to the intercooler free of debris?, soil/mud or insects, a pressure hose should clear these easily if blocked. Degrees Circa 20c would be what I would expect to see as a nominal difference, but dependant on load as so far as the amount of boost and load on the engine (heat generated and transferred to induction air from the turbo) would vary this. I am pretty sure the MAF circuit uses IAT to calculate air mass so there is a chance this may be the issue as inside some MAF’s there are temperature sensing devices. As the vehicle is almost new in mileage terms you are pretty much looking at electronic component malfunction other than mechanical issues. My guess would be to suspect MAF out of range if the reported air temperatures were seemingly incorrect and all other sensors had been changed. Its a tricky one if the only codes pulled were P1548!

  38. Thanks for the really helpful description of turbo operation and limp home.
    I have a 2003 316cdi motor home with less than 40,000 miles on the clock.
    A couple of months ago it went low on power but was ok again after restarting the engine. The same happened again a week later and it would not go above 3000rpm. After restarting it revved up to about 3000, then 4000 after depressing and releasing the clutch. The turbo actuator moved ok. I couldn’t see anything odd although I thought the air temperature sensor was rather oily and carefully cleaned it. There doesn’t appear to be an MAF or EGR and there is no air conditioning. I haven’t checked the pressure sensor.
    Today, I find that it won’t rev above 2800 when stationary even after depressing the clutch although the turbo actuator moves when revved. But when I drive it seems ok up to 4000rpm. There have not been any warning lights.
    Any thoughts would be appreciated before I decide what to do next.
    Thanks, John

    1. Hi John,
      If you have seen rev limiting to 2800 after a restart and clutch depression, (and you have no problem starting the vehicle) chances are your limp home is caused by fuelling. Try replacing the diesel filter for a Mercedes OEM Filter of the correct type, this is the first thing I would do along with checking the air filter was not choked. It would also be worth a look to see if kids have stuffed something up the exhaust as a prank! You may have an intermittent clutch switch or brake light switch, both cheap and easy to replace.

      Your model will not have a MAF or EGR so rule them out of your investigations.

      Check all turbo hoses for any oiling up at connection points to the intercooler, inlet manifold and coupler (with sensors in) on the right when looking into the engine bay. Any black oily deposits here is a sure sign that something is leaking. Take off the hoses, clean them up and retighten. Make sure the long hose across the top has not split underneath where you don’t look. This is the usual place for this to happen.

      Hope this helps

  39. Thanks for the amazingly fast response! It will be a few days before I have another look but I have recently started using premium diesel to see if it gives me better fuel consumption (not convinced yet!). Now you mention it, I did notice a few very small air bubbles in the fuel line. Several years ago I did have problems due to a non oem filter being fitted but that caused serious air bubbles and starting problems. Garage had to come out on that occasion to remedy. So maybe a fuel filter issue this time. I’ll have a look at the filters next. Thanks again, John

    1. Hi John,
      It may be worth a look at replacing the black non-return valve on the top of the fuel canister filter. This part is about £5.00, they often crack (almost invisible hairline cracks) this lets in air to the sealed system, often the O ring here between the return valve and filter body passes air – but to be honest I would have expected extended cranking times with this issue on a cold start, as generally the fuel is allowed to drain back to tank while standing due to to poor sealing of the fuel system. Anything is possible! If you have the fuel filter with the ‘water in fuel sensor’ditch that and use the sealed canister type, as the base sealing is flakey on the sensor to say the least – Simply unplug the sensor, sling it and tape up the connector tucking it in above the thermostat housing, neatly out of the way.

      All the best

  40. Thanks again. I’ll give it a good dose of looking at later in the week and hopefully may be able to post something useful to others as a result. John.

    1. Hi John,
      Thanks for the purchase of the book, did you manage to down load it OK as a few people have difficulty with the link, probably because its quite a large file and they give up. Any issue let me know and I will send you a .pdf over directly. Let me know what you find with the filter.
      All the best

  41. Hi Steve,
    I had a look at the things you suggested and it appears my problem is the clutch switch. When I checked it with a meter off the vehicle it was sticking closed. Tried it again on the vehicle, depressed the clutch and gave it a tap to open the contacts, released the clutch and 4000 revs again. So, hopefully a new switch will sort the limp home issue. I’ll let you know! Thanks again for your advice.

  42. Hi fellow travelers.Have read and tried all ? of the above.I have a Sprinter 903 4 cyl 2000 model.Ex hire motor home.Have just fixed a dose of black death on # 2 injector,all 4 pulled and cleaned.Motor starts straight away and will pull 4000= rpms with clutch actuation.I have an after market turbo boost gauge installed and it tells me boost has not changed (18 psi).Put clear hoses in fuel system to check for air.No difference.Changed fuel filter and installed 12v booster fuel pump in system still no change.Removed air cleaner still no change.Exhaust system sounds the same no signs off restriction,straight thru muffler system.So PLEASE any ideas ???.
    With thanks Frank.
    From Western Australia,

    1. Hi Frank,
      You really need to look at live-data on diagnostics and see what the rail pressure is doing. I have had faulty fuel rail pressure sensors do a similar trick. That is my next suggestion – real code read diagnostics!
      All the best

      1. Thanks Steve.Diagnostics x3 only tell me bad glow plugs which is not a problem in this climate.Diagnostic was not mercedes star.Have ordered cheap sensor on evil bay to see if that will help.Will keep you posted.

  43. hi i have a 2001 sprinter thats causing me some grief. it seems like a a mixture of vacuum leak & something temperature related
    so my van goes in to LHM after 2hours ish of driving. its also sticking in gear a bit now to as its an auto but thats another story
    so i checked the vac line going to the cabin recerc solenoid. it was broken.
    its fault code was saying P1470-004
    charge pressure control valve
    its a $400 part to get the valve, i take it thats the black thing under my airbox?
    I’ve had the injectors changed and fuel pump. a $3500 exercise i probably shouldnt have done .
    apart from boost control valve and intake air temp & pressure sensors is there anything I’ve missed ?
    I’m going to try and get another code read done on it but I’m getting fed up of buying mercedes parts although engine consumables here in australia were actually fairly reasonable in cost

    1. Hi Ryan,
      You will find some detail of that recirculation air flap actuator here. If you can seal off the brown hard supply pipe to it and the fault was related to vacuum loss the engine should now run properly, if not and the fault is still present it could be some thing else. Do leave the flap blocked off as any vac leak will have detrimental effect on whatever else is connected to the circuit. There is the outside chance the internal mechanical parts of the VNT turbo are sticking or faulty, if you have time and care you dismantle it and clean up the internals. See here.
      I hope that is a little use to you.

      All the best

  44. Hey there . I bought my Mercedes sprinter 2004 313 CDI in the Limp Mode but I managed to drive it from Sydney
    to Adelaide . with no problem .
    After a week of trying out everything else it did turn out to be the Turbo Boost Solenoid actuator .
    Like everyone says it wont rev over 3000 RPM . I was lucky to find one out of a wreck and installed it .
    PRAISE THE LORD IT WAS A CHEAP FIX . I RECKON GO TO THIS FIRST AS IT FIXES EVERYTHING ITS NOW SELECTING THE AUTO MODE AS WELL . all good . What a magnificent vehicle heaps of power , lots of room . Beautiful .

  45. hi Steve
    i have a 1999 mercedes benz 110 cdi vito which is in limp mode. it is also raising its temperature. is it related in any way?

    1. Hi there McDonald.
      See if the engine is actually overheating, if not replace the coolant temperature sensor and thermostat/housing. If the ECU read temperature is too high it will limit the engine by putting it into limp Mode.
      All the best

  46. Hi Steve,
    Great advice given to all on here good on you. ?
    I have a 2003 vito 110cdi and its recently developed a intermittent fault when driving along sometimes the throttle pedal is unresponsive could be at any speed o specific timings and is bit dangerous on the motorway although no lights come on dash and then after a few seconds pedal becomes responsive again.
    It does not have a maf sensor, would really appreciate your expert opinion.
    Thanks very much

  47. If you change the cam shafts sensor do you first have to clear all the faults on the diagnostics before it runs again

  48. Hi Steve,
    I have a 516 Cdi 2011, vehicle 6 months ago starting misfiring consistenly, limp mode when cruising at highway speeds, finally a rewire of one of the injector plugs using repair kit from Mercedes solved issue, but would still come on sporadically once a week.
    At regular service, ask mechanic to re check it, found black death, pulled out injectors cleaned, new washers etc, put back together and now getting codes P215000 AND P214700 (Power supply ground issue to group a and group b). vehicle appears to start up on 3 cylinders. switch off and restart, and all good, can clear code and drive as normal. Can even stop, and restart, no issue. But if left for 5 or more minutes, MIL light and rough start, and longer start.
    We have checked wiring, and rewired repair kits to all injectors, as black death caused issues with connectors, no change.

    Independent now want to install a complete wiring harness, and 4 new injectors, but I am not convinced this is the answer. Any suggestions?

    Thanks in advance

    1. Change- only getting P215000 consistently, and if you turn the key to on without starting for 5 seconds, then turn off, and start immediately, no codes no fault. New battery installed also thinking it may be a voltage issue, as previous battery was on its way out, no change.

      Any thoughts would be greatly appreciated.



      1. Shane,
        There is a ‘Y’ configuration to the battery positive cable where it splits off to the starter and fuse board, This can corrode and give rise to power related issues. Very popular fault, check it out.

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