Limp mode on Sprinter 311 cdi W903 2003

[Davebuck]

Hi, I have been in what I believe to be limp home mode occasionally since I bought my 2003 sprinter 311 3 years ago but it always reset after a short stop. Van has now been permanently in LHM for 2 weeks for no obvious reason. No dash lights show up, several Star codes show up including MAP sensor problem. Watched Florida Man video on TN1 which showed that a good MAP will move linkage on turbo but disconnected or bad MAP will not produce any movement there. Difficult to see direct comparison with my 311 W903 sprinter since nearest equivalent – the Boost Pressure Sensor is on far side of intercooler whereas MAP on TN1 video is close to air filter box. Nevertheless I tried disconnecting then re-connecting this sensor, the Turbo Boost Valve Pressure Converter (which has vacuum pipe direct to turbo) and the ENGINE AIR INTAKE SENSOR, which is very close to air intake filter box. None of these moved turbo linkage between impeller and fan whether connected or not while engine idle or revving. According to video this would show MAP sensor was faulty. But before ordering all 3 of above sensors I manually moved turbo linkage and this had no effect whatsoever on engine revs, again either while engine idle or revving. Does this mean turbo itself is faulty or can revs be kept capped by ECU even tho I was manually trying to kick in turbo? Would welcome any thoughts!

 

[clarkmichigan55b]

Good morning,
I first port of call would have been Florida van man he has highlighted the common faults with this model
Have you checked all vacuum pipes for splits collapsed pipes etc i assume air filter and inlet pipe work is clear.
Check the turbo spins freely and no movement in the bearings.
The only other thing i have noticed with the vans on his channel is that they seem to be automatics i dont know if this make a difference to your problem.
Have you checked the EGR valve

 

[Davebuck]

Many thanks for response - yes need to check vacuum system all over van I believe you can get repair kits for diaphragm on turbo itself? My garage have offered to do some midi(?)-vacuum test on that to see if acctuator functions, they will also smoke test intercooler as tgey reckon even a pinhole leak can trigger a limp mode! Presume easiest way to see turbo spin is to remove rubber hose from output port of turbo? My van is 5 speed manual which I presume means ECU can't know what gear I am in, only wheel revs? Thanks again for advice, I may well be back for more!

 

[mersum1es]

I blieve if your engine is at limp mode even before starting, that prvenets turbo actuation. Like said, can be several things from vacuum pressure/ vacuum controller problems to sensor problems. If you have star, there are guided troubleshootings for every code!