Mercedes E class 220 cdi engine trouble

[Adrian_Merc]

I have 2001 mercedes e class 220 cdi and recently i have been getting loss of power at random times and now the car has a very rough idle and engine shakes quite alot . when it cold it sounds like it nearly going to die out . The miles on the car is 181k

Could any body advise me what could be wrong with the car and how much would it cost to repair the car . i been told it could be the timing chain ,

please help

 

[BoyracerAU]

I would check all the sensors to make sure they're plugged in correctly as a start.

My car was idling roughly not long after I got it back from the mechanics and I discovered a sensor on the air intake had slipped out. I plugged it back in securely and all was well.

Fingers crossed your problem can be as easily sorted!

 

[Tinkerer]

I had the same problems with mine so bought a new MAF sensor off ebay this cure the limp mode and rough running but left the car surging when in traffic between 30-40 mph.

So did an Olly on it and had it checked out on Star, finger pointed at MAF sensor 'why did I not buy from MB' basically because the quoted £232!! and on on ebay was £50 took the old MAF sensor to MB and they then charged £70, it worked fine no more surging and smooth gearchanges but still runs really rough on a neutral throttle so.... Star also pointed the finger at the EGR valve which I had cleaned earlier but the man at the garage said it was probably not shutting off completely which will make it run rough at low throttle openings.
New EGR ordered from MB £200 and will fit next week, I will let you know if it works.

 

[Tinkerer]

Quick update, seeing as its a nice day thought I would have a little tinker, anyway, took the vacuum hose off of the top of the EGR control unit and plugged it with a 5mm drill bit to stop any crud getting in .......... result ........ no more rough running!! I might just leave it like that after I fit the new valve unit.

 

[Tinkerer]

Forget most of that, running smooth, not surging but still dropping in and out of limp mode!

 

[Tinkerer]

OK so yesterday I finally got the correct EGR valve (now called a gas mixing chamber!) out of merc ,£141, fitted it today which took about an hour because I did not have torx spanners to do those pesky bolts that fix the bracket to the EGR.
The old EGR had a lot of soot in seeing as it was only cleaned about 2.5 months ago but I guess was witness to the fact that it was not working properly.
Took it for a 15 mile run afterwards and fingers crossed, nice smooth running and no limp mode.
Would not have thought that the EGR could trigger limp mode but the indy told me that the MAF had logged plausibility errors which may have made it think that the MAF was still faulty after I had replaced it because the EGR was letting gas by when it should have been closed.

 

[Dieselman]

The EGR valve will trigger limp home as it's operation is monitored by the MAF sensor.