P0402/P0299 Codes and Limp Mode - W204 C250 CDI
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C250 CDI
P0402/P0299 Codes and Limp Mode - W204 C250 CDI
Hi Guys!
New to the forum, just thought I'd post up an issue I'm currently having with my 2011 W204 C250 CDI (OM651 2.2L Twin Turbo).
I was driving home from work and noticed that my throttle pedal suddenly stopped working. Confused as to what was happening I realised that the car had gone into a limp mode of some sort and therefore went to stop by the side of the road. I tried restarting the car numerous times but found that the car would drive normally for a little bit before returning to limp mode again.
Long story short, and many hours by the side of the road later I had the car towed back home. I then pulled out an ELM327 bluetooth OBDII sensor and tried some apps to diagnose the problem.
This resulted in an P0402 error code being thrown (Exhaust Gas Recirculation Flow (EGR) Excessive Detected). I did some research and found that it was quite common for this valve to go bad in Mercedes diesel engines and quickly purchased a replacement online.
The following morning I decided to start the car up again to see if things were still the same. A quick drive down the street and the car once again went into limp mode, however this time started shuddering severely. I stumbled back to the garage once again and tried the OBD reader, which now was showing me a P0299 code (Turbo / Supercharger Underboost, the P0402 code was also now not present anymore
). I had a quick look around the engine bay for boost leaks from vacuum lines/intercooling piping but don't really know where to begin to be honest!
The car will most likely be getting towed back to the dealer this week, however I thought I would just post this up to see if anyone out there has any experience or ideas as to what could be the issue.
Thanks in advance guys, any help would be greatly appreciated!
New to the forum, just thought I'd post up an issue I'm currently having with my 2011 W204 C250 CDI (OM651 2.2L Twin Turbo).
I was driving home from work and noticed that my throttle pedal suddenly stopped working. Confused as to what was happening I realised that the car had gone into a limp mode of some sort and therefore went to stop by the side of the road. I tried restarting the car numerous times but found that the car would drive normally for a little bit before returning to limp mode again.
Long story short, and many hours by the side of the road later I had the car towed back home. I then pulled out an ELM327 bluetooth OBDII sensor and tried some apps to diagnose the problem.
This resulted in an P0402 error code being thrown (Exhaust Gas Recirculation Flow (EGR) Excessive Detected). I did some research and found that it was quite common for this valve to go bad in Mercedes diesel engines and quickly purchased a replacement online.
The following morning I decided to start the car up again to see if things were still the same. A quick drive down the street and the car once again went into limp mode, however this time started shuddering severely. I stumbled back to the garage once again and tried the OBD reader, which now was showing me a P0299 code (Turbo / Supercharger Underboost, the P0402 code was also now not present anymore
). I had a quick look around the engine bay for boost leaks from vacuum lines/intercooling piping but don't really know where to begin to be honest!The car will most likely be getting towed back to the dealer this week, however I thought I would just post this up to see if anyone out there has any experience or ideas as to what could be the issue.
Thanks in advance guys, any help would be greatly appreciated!
