Engine diognostics???? Limp home mode

[lukester2002]

Thanks, I will keep you updated

 

[lukester2002]

:bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana:

Thanks to all you guys on here, I finally have some good news.

First I would just like to say that HARE MOTORS HALIFAX tried ripping me off good and proper. After charging me £150 and quoting me £1000 and £600 if the problem didnt go, to fix a fault that they claimed had showed up on their "Mercedes" computer.....

Well in the end after they tried to convince me that the main dealer would "have my pants down" if I went to them (the main dealer).... I decided not to listen to them and listen to you guys on here. Which I cant say how grateful I am for your help. I went to the main Dealer in Huddersfield and they offered the best service I could have imagined, by immediatly finding the fault with their REAL Mercedes computer and guess what??? ...... It was simple, a split vacuum pipe, that cost £8.

Despite them telling me these had been checked at HARE MOTORS. As I have come across this problem in a previous car. Just a word of warning guys. And also they told me that oil on the electronics was one of the problems, well, it just seemed to appear from nowhere a nice clean oil patch... coincidence???? I dont think so as this was nothing to do with the cause of problem.

Anyway on a more positive note, I would like to thank alll you guys for having the time and patience to look at and reply to all my questions. You have saved me god knows how much and made my day. I will regulary check these forums and help as many people as I can in the future.

Thanks

:bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana::bannana:

 

[carat 3.6]

Glad your car is now fixed, now you can enjoy the mercedes driving experience

 

[BlackC55]

So it was an engine fault! Glad you got it fixed. I bet it was the pipe from the turbo actuator to the vacuum transducer?

 

[lukester2002]

Yeah, I believe it was that pipe. Seriously guys I cant thank you enough. Its unbelievable how helpful you's have been. And it drives llike a dream. I am well chuffed

Thanks again

 

[The Dent Guy]

Hi guys - im reigniting this thread as I appear to have the same problem. However, my car is the facelift 2004 C220 CDi, which has minor differences.

That being - no vacuum pipes.... or so I think.... ie it has the Electronic turbo actuator and EGR.

Been to 2 indies with star machines and neither found codes. Finally went to MB main agent 6 weeks ago and asked them to tell me the fault codes. They did what they called a "short test". Half hour later they showed me a printed piece of paper showing MAF sensor reading at value of 486 when it should be reading 285-325 and claimed this was the cause of limp mode. I asked if it was in limp mode whilst testing and they confirmed it was. They were eager for me to order the new MAF.

Anyway, I bought a new genuine Bosch MAF from euro car parts and fitted it myself. It didn't work!

Then I discovered that a faulty EGR can throw wrong readings to the MAF so I changed the EGR and also it didn't work! The EGR was only lightly coked and was very free moving. I tested it with the cover removed where the claw pushes the valve down.

Another point to note is that I have had an induction smoke test and no leak was found but the turbo whistles excessively in my opinion.... could this be a big clue?

Also I had the DPF "emptied" at 125k and mapped out of the ECU. Car still has varying intermittency with limp mode but mainly when car is restarted at full temperature. Other times I can go for weeks with no problem - and also can go weeks with limp mode whether its stone cold, lukewarm or full temp.

I had the "turbo revive" treatment at about 135k which made no difference and have recently watched the turbo vane actuator working in both limp mode and full power conditions.

Car has now done 164k - intermittent limp with no management light. It all started just before I emptied the DPF. In fact, there has been no engine management light at all since the problem started 3 or 4 years ago.

I have noticed the crankcase breather to turbo inlet has a 'T' shaped sensor at the turbo end which is totally covered in thick oily gunge. But, not on any of the exterior of any pipes. If this breather pipe is blocked, could this cause more air to be drawn past the MAF, thus a high reading and limp mode?

Also, are there any vacuum pipes im unaware of that could give intermittent limp mode even though the turbo and EGR are electronic?

Many thanks in advance - I've done tons of research but this is becoming a money pit.

Please help.

ps.
Just to add, it is definitely the electronic variable vane turbo and electronic EGR.

 

[BlackC55]

Is the intake clogged?

 

[Auto-mobile]

I have had a customer with the dpf deleted out of the Ecu, no fault codes and severe lack of power, I had the customer take it back and have the original map put back on, then there were 4 fault codes.

 

[The Dent Guy]

Is the intake clogged?

Are you meaning the intake pipe on the turbo? Or intake manifold?

Added photos of gunge on the sensor on the crankcase breather.

Also I noticed the intake pipe off the turbo slid off easily.

ps. What does that sensor do... temperature? or pressure?

 

[The Dent Guy]

I have had a customer with the dpf deleted out of the Ecu, no fault codes and severe lack of power, I had the customer take it back and have the original map put back on, then there were 4 fault codes.

Are those codes related to the DPF when put back to factory map?

Im assuming the DPF was physically removed (ie. cut open and emptied, then welded back up like mine).

 

[Auto-mobile]

There was a dpf fault, which was obviously overlooked as it wasn't there, but there we're boost related faults (turbo actuator) and egr.

 

[The Dent Guy]

There was a dpf fault, which was obviously overlooked as it wasn't there, but there we're boost related faults (turbo actuator) and egr.

Can the electronic actuator be faulty even if it appears to be working, regardless of whether in limp or full power mode?

 

[The Dent Guy]

Can a blocked crankcase breather cause limp mode?

What is the purpose of the sensor in that same breather pipe which attaches to the turbo induction main hose?

PS that main induction hose slips off the turbo with ease. I guess it needs tightening and a new orange seal.

 

[The Dent Guy]

Update:

I have removed the crankcase breather pipe and the induction hose from MAF to turbo and the electronic part which I now know to be a heater for the breather pipe.

All parts coated with a film of oil but no sludge or blockage at all.

Thoroughly cleaned and reassembled - this time I managed to tighten the jubilee clip at the turbo inlet (orange seal here is fine).

The turbo is almost inaudible from inside the car now, which is good... but its still in limp mode.

Does anyone know of any vacuum pipes? Even though its the DPF version with electronic actuator and EGR?

ps. thanks for your answers so far.

 

[The Dent Guy]

I have had a customer with the dpf deleted out of the Ecu, no fault codes and severe lack of power, I had the customer take it back and have the original map put back on, then there were 4 fault codes.

A shout out to Auto-mobile.... I had two remapping companies remap the ecu and neither tripped any codes on star. But finally put the standard map back as suggested and then put back on star to find the egr and the dpf differential pressure sensor were faulty. So both changed and the dpf remapped out again. Finally solved.... many thanks.