Hi steve ,thanks for the reply have been busy with work lately but we plan to go away in a week or two so I thought I had better look at the van again.took It up the motorway today but there does not seem to be any boost from the turbo.At home I have taken the air box off to check for any thing obvious.There is a tiny air leak from somewhere,but the van has always had this slight leaking sound after turning the engine off, it lasts about 1 min then stops.I have traced it to the turbo boost actuator valve.Heres the brain stormer……if I disconnect the tube from the turbo boost actuator to the vacuum actuator,and place my finger on the connection under the turbo boost actuator ,where I had pulled the tube from, the air leak stops and I feel a suction on my finger.If I start the van with the pipe still off the vacuum actuator not alot seems to happen but If I keep the pipe off and then put my finger back on the bottom of the turbo actuator the air intake sounds like a turnado, if I pull my finger off again the rushing sound goes again.So is the boost actuator at fault or is the vacuum actuator leaking air to the turbo actuator?The connection pipe between the two seems okay.Many thanks.Russ

Hi Russ,
The MOT blast should not really have caused any issues, its more likely if it is connected to this event that a Turbo boost hose is leaking or is split allowing boost to escape. On this age of vehicle not always does an EDC lamp illuminate. Check all the hoses and connections post turbo, as I have stated before look for black oil staining as this is usually a dead give away to the location of a boost leak (especially on the intercooler entrance and exit pipes). Check the vac connections are sound and that the turbo actuator moves on a rev. (No movement = no boost being called for) The manifold/boost pressure sensor may be faulty / misreading, its a cheap component in the big scheme of things and is well worth a swap. Really all the fault codes will be stored, if you can get them read and then just rectify ‘exactly’ what is indicated as the problem and see how you go. Often £40 spent at an independent for a code read at this stage will save you a great deal of time and money in the long run.
Good luck, do let me know how you get on.
All the best
Steve

Hi Yusoff
Try here : http://www.mybenz.org/zoopp/html/modules/mylinks/viewcat.php?cid=8
Regards
Steve

Hi Mike,
It does seem that the boost pressure is up and down, or at least the reported signal to the ECU is, that P1470 indicates that. Give the pressure sensor a try, I have indicated the position of this on the T1N Sprinter in the write up somewhere and am pretty sure you will find it in a similar location. I think often even the ‘so called experts’ are baffled by what they see on the code reader, the truth is they are and have been trained to use that alone, all the old fashioned fault finding – understanding the principals of what is happening – now plays little part in modern diagnostics. Indeed often a problem with one element will cause an indication on the code reader that is more of a result of the problem than the cause! I have always found it better to try and understand the issues along side what the ‘magic device’ tells you, this way you get a better focus on the problems at hand. (My two pence worth anyway)

There are two switches at play on the pedal box, the first is the clutch switch that stops the vehicle being over revved when stationary, this can be over ridden by the ‘up down method’ to test and see if the engine will rev over 3000, in other words see if it is in a fault condition without showing an EDC light etc. The other is an area that may be worth a look is the brake light switch. This is a dual switch and lies not surprisingly above the brake pedal. This not only provides the signal to the rear stop lamps but there is a second set of contacts that tell the ECU that the vehicle is being retarded and signals not to apply boost. You can test this out on a vehicle that is working correctly, drive in 3rd gear at a medium pace, then cover the brake with your LEFT foot and while applying gentle pressure to the pedal, try and accelerate with your right foot on the throttle – it will not allow you to and the engine stumbles! I suppose this is a ‘fail safe’ that if in an emergency braking condition you stamp the boards, catching the throttle with your size 12s would not make any difference to the level of stopping distance. I am pretty sure that it is just a safety feature. The dual switch body is a known trouble spot, just because the brake lights work, does not indicate that the secondary part of the switch is functioning correctly. Could be worth a look – its known but rare that this gives problems – but who knows!

The ‘T Piece’ device with a pair of wires to it you can see in the crank case breather hose, where it joins the turbo inlet pipe (from the air box) is in fact a small heater ! This operates in extreme low temperatures to stop water vapour or emulsion from freezing in the pipe blocking the crank case breather so I doubt that this will be the source of the problem even though its supply is in the suspect loom section, unless of course it is shorting out and causing fuses to blow etc.

I hope that helps you out Mike, keep in touch and let me know how you get on. I am about to go and change a disc and pad set on a LWB 313 this morning and then onward to a front spring and leg on a Clio, so a busy day ahead – hope the weather stays good.

All the best
Steve

Hi Bill,
As you have probably read there is a great deal that can cause the issues you have. With regard to the turbo itself, you are correct that it either spools and compresses or it does not, but there is a middle ground – does it produce enough boost to always be in the required load range (worn turbo) or is the actuating mechanism intermittent causing an occasional no boost condition that sets the vehicle into LHM. I am suprised in many ways that the performance returns only on a ‘code reset’ because normally the codes would be recorded and once the problem was rectified or had righted itself (if intermittent), then normal driving condition should be resumed without further intervention. Maybe that is a pointer to the problem?. Check the connections to the ECU for corrosion as water is known to get through the bulkhead grommet and run down the loom into the ECU connectors. If you see a problem here, clean up the contacts and connector blocks then prevent further water ingress. (Worth a look as I have been caught out with unusual gremlins caused by this fault before)

Maybe I would also look to swapping out the MAP sensor in the induction pipework post turbo, or at least cleaning it with some carb spray to see if there is any improvement. This is a common device that fails regularly by reporting incorrect boost pressures to the ECU and it could just be the problem.
Let me know how you get on.
Best Regards and good luck
Steve

Hi Mike,
If you have checked most of things mentioned in the blog post then it may be a fuel pressure or fuel pressure sensor problem. There is a pressure transducer that lives in the end of the HP fuel delivery rail and it is quite common for the two ‘O’ ring seals to perish and cause some issues, although usually its more to do with starting than low boost. However the most sensible thing to do would be to get an independant garage to read the vehicle and list you the fault codes – go straight in and sort the defined issues instead of the ‘scatter gun’ approach that often runs away with money at a great rate of knots.
There is one other thing that I have had cause similar problems – on the right hand side of the engine under the bonnet, beneath the inlet manifold you will see the low pressure fuel delivery sensor in a T piece connector. This has a connector that faces down toward the road and often becomes loose or a poor connection, should this electrical connector become disconnected or corroded, the ECU gets a ‘high fuel delivery pressure’ signal and cuts back the vehicle into LHM. I cannot say that this will be the cause but on more than one occasion now this has been the problem and is well worth the short time to check before moving on.
You may wish to have a look at a fellow posters information here: http://sprinter-source.com/forum/showthread.php?t=7173 there is a few pointers and suggestions for you to try without me retyping. I really think the best advice would be to get the fault codes read and move forward from there.

I hope you get sorted, do let me know what you find.
All the best
Steve

Hi there,
It may just be worth removing the radio and disconnecting the power for a short time to reset it, should it have locked up the processor. Although from what you describe I do think that there could be a more serious problem with the unit and maybe a specialised repair will be nessesary.
All the best
Steve

Hi Duncan,
It would be good to check induction hoses for leaks, especially at the joins/hose clips to the intercooler. Usually oil staining indicates a boost leak at the joints. Make sure the vac hose to the turbo actuator is not split and is a good fit on the spigot. Check out the other fault finding tips in the post and let me know how you get on.
All the best
Steve

Hi there,
My suggestion would be to check all hose connections on the induction side, post turbo. It sounds if you may have a boost leak under heavy load. Check all the hose clips to and from the intercooler, if you see oil staining/film around the joint there is a good chance you have found the source of the leak. Check also the large induction hose that goes to the inlet manifold, this splits underneath, along its length where it escapes casual inspection by eye. Take the hose off and look for faults by flexing the hose between your fingers. I will place my money on this being the problem. Good luck.
Regards
Steve