oldschool2011
New Member
- Joined
- Jun 16, 2011
- Messages
- 2
- Reaction score
- 0
- Location
- UK
- Your Mercedes
- E200K 2004, previously 230TE 1991; C180 1999
Hi guys I am new to this and wondered if anyone can point me in the right direction.
My E200k engine light came on earlier this year and my garage said it was the airflow meter. It was cleaned and reset and my garage said that if it comes back on then they would need to replace the airflow meter.
The light came on and it was also drinking a lot of petrol. Took it for an MOT and it failed on emissions. They say it’s running rich – the car thinks there is more air coming in and is over compensating with fuel but my garage said that its not the airflow meter.
I have had the lambda sensors replaced last year (both), Mercedes say cat needs changing. However garage didnt agree and found that both breather valves were broken so replaced them. Still didn’t fix the problem.
I had both cats replaced (non merc) and this hasn’t fixed the problem. They have unplugged the computer for an hour but no result.
The problem is when they test the emissions (in an MOT) the CO level is at 3.14 and the lambda at 0.91. If they race the engine the CO comes down to 1.20 and even 0.07 but then the lambda shoots up. The engine light eventually comes back on and the computer says lambda upstream fault – permanent but when they clear the code it will come back on again after a while (usually when the engine is in high rev to test the emissions.)
I’m at my wits end – I would be grateful for any ideas. At the moment it is being tested to see if there is an air leak in the system. Thanks again
My E200k engine light came on earlier this year and my garage said it was the airflow meter. It was cleaned and reset and my garage said that if it comes back on then they would need to replace the airflow meter.
The light came on and it was also drinking a lot of petrol. Took it for an MOT and it failed on emissions. They say it’s running rich – the car thinks there is more air coming in and is over compensating with fuel but my garage said that its not the airflow meter.
I have had the lambda sensors replaced last year (both), Mercedes say cat needs changing. However garage didnt agree and found that both breather valves were broken so replaced them. Still didn’t fix the problem.
I had both cats replaced (non merc) and this hasn’t fixed the problem. They have unplugged the computer for an hour but no result.
The problem is when they test the emissions (in an MOT) the CO level is at 3.14 and the lambda at 0.91. If they race the engine the CO comes down to 1.20 and even 0.07 but then the lambda shoots up. The engine light eventually comes back on and the computer says lambda upstream fault – permanent but when they clear the code it will come back on again after a while (usually when the engine is in high rev to test the emissions.)
I’m at my wits end – I would be grateful for any ideas. At the moment it is being tested to see if there is an air leak in the system. Thanks again
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