Possible EGR issue due to low power

[kolobos]

Hi Guys,

My w203 C220 CDI 2004 is having a few issues with power, as such it feels like the turbo isnt even working. If i fully press the accelerator it doesnt change gear nor does it speed up a great deal either. However after being sat in traffic for 5 to 10 minutes it suddenly appeared fine once again. Also prior to a run I could smell burning and a bad gas type fume, although this only happened once.

I believe I may have an EGR fault as STAR Diagnostics indicated a few errors when my glow plug relay was changed and the faults cleared. Perhaps the EGR valve is now the problem?



Steve.

 

[optimusprime]

Hi not sure but most EGRs .. are cleanable The small pintel inside gets blocked with carbon .

 

[a111r]

Hi not sure but most EGRs .. are cleanable The small pintel inside gets blocked with carbon .

All EGRs can be cleaned out.

Pintles is injectors, btw.

 

[toteimerced]

Check the intercooler/boost hoses for splits, it can throw up al sorts of codes, my lower left intercooler hose had a 40mm split in it and gave the same symptoms you are having.

 

[kolobos]

UPDATE:

Car is still currently with the Indy mechanic/garage. The EGR valve was non operational so a new one has been fitted. However, the engine is still missing a beat now and then or when sat idling. The glow plug relay and glow plugs have been replaced as the relay was u/s.

Current thoughts are that one of the injectors is not holding the fuel pressure and allowing fuel to run back. Sometimes starting also takes too long. Car is currently awaiting fuel line and injector tests.

Steve.

 

[coneybiller]

2004, don't suppose this would have a DPF? Was wondering if the car was trying to perform a regen cycle. Hence the hot burning smell and lack of power. It will be creating excessive heat by using excessive fuelling in the exhaust system to burn off the carbon build up in the DPF canister. BUT that would throw a code up I would of thought! That and I'm not sure if yours will be new enough to have a DPF fitted.

 

[kolobos]

No DPF on my model.

Injectors tested out OK including fuel pressure regulator but car still experiencing rough idling or missing occasionally. Car is also fully serviced, I will speak to my Indy later today as they have had it a week now and struggling for a cure?

Steve.

 

[a111r]

Same problem on mine. I'm thinking the turbo's VNT mech might be sticking due to carbon build up.

 

[SteveFromAvantgarde]

What specific fault codes do you have?

 

[a111r]

UPDATE:

Car is still currently with the Indy mechanic/garage. The EGR valve was non operational so a new one has been fitted. However, the engine is still missing a beat now and then or when sat idling. The glow plug relay and glow plugs have been replaced as the relay was u/s.

Current thoughts are that one of the injectors is not holding the fuel pressure and allowing fuel to run back. Sometimes starting also takes too long. Car is currently awaiting fuel line and injector tests.

Steve.

Did your previous STAR test not check the injectors' leak off status (the QCV) ?

 

[kolobos]

STAR reported no errors or fault codes.

 

[kolobos]

After lengthy tests and a number of parts swapped and changed for fault finding it would appear that the fuel rail is at fault despite STAR reporting no errors. The Indy mechanics have replaced the fuel rail and report that everything now appears normal. They are currently testing it and hopefully I will get the car back tomorrow.

Does anyone know how much a new one is?

Steve.

 

[ampwhu]

been having the same problem with mine.

mine is a late 2005 (54 plate) C200 and I occasionally get limp mode. if I pull over and turn the car off, when it restarts it is fine.

so I plugged a scanner in and it said something about the 'air mass being too large'. P2355. everyone said EGR valve. twice I have had it out and cleaned it and twice it has not resolved it. the pin in the EGR moves freely.

so when the EML came on, I removed it with my scanner. It then drove fine for 2 weeks. it then re-appeared. I decided to take it to one of these "indys" that everyone goes on about. he plugged it into his machine and couldn't find anything wrong with it. he test drove it and couldn't find anything wrong with it. so I drove it away.

2 weeks again, no problems. then last week, you guessed it. limp mode. turn it off and then back on again, hey presto, no problem since last Saturday.

last resort for me is to remove this EGR and take a look under the electrical box on the side of it. must be a wiring issue. car still has no fault codes and drives fine. maybe when I plan to travel in 2 weeks, i'll suffer the same again!

 

[kolobos]

been having the same problem with mine.

mine is a late 2005 (54 plate) C200 and I occasionally get limp mode. if I pull over and turn the car off, when it restarts it is fine.

so I plugged a scanner in and it said something about the 'air mass being too large'. P2355. everyone said EGR valve. twice I have had it out and cleaned it and twice it has not resolved it. the pin in the EGR moves freely.

so when the EML came on, I removed it with my scanner. It then drove fine for 2 weeks. it then re-appeared. I decided to take it to one of these "indys" that everyone goes on about. he plugged it into his machine and couldn't find anything wrong with it. he test drove it and couldn't find anything wrong with it. so I drove it away.

2 weeks again, no problems. then last week, you guessed it. limp mode. turn it off and then back on again, hey presto, no problem since last Saturday.

last resort for me is to remove this EGR and take a look under the electrical box on the side of it. must be a wiring issue. car still has no fault codes and drives fine. maybe when I plan to travel in 2 weeks, i'll suffer the same again!

Well I never imagined the fuel pressure rail would cause me so many problems and i think it was just bad luck that the glow plug relay and EGR failed at the same time. My indy did not recommend trying to clean the EGR valve as they can soon fail again and as it turned out it was non responsive anyway, so it was replaced. Its difficult when STAR diagnostics reports no errors and with Mercedes I wouldn't trust anything other than STAR.

Steve.

 

[ampwhu]

i'm not convinced. my scanner picked up the code that this 'star' didn't.

 

[kolobos]

Solved

I finally got my car back today and the main issue was indeed the fuel pressure rail. The garage have lent me their spare until I can source a good second hand one. New ones are a fortune and I have already spent over £1,000 so I do not want to buy a new one unless absolutely necessary.

Steve.