Lord_Langers
Member
- Joined
- Jan 27, 2018
- Messages
- 10
- Reaction score
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- Your Mercedes
- 2005 S320 CDI
Hello all,
Well, the honeymoon period is definitely over with my new W220. She's a 2005, with the OM648 I6 engine and 140,000 miles.
Coming home from work on Thursday evening, I slowed down from 70mph at a set of traffic lights, and when I went to pull away again, the car was obviously in limp mode - slow acceleration, gearbox goes up through the gears quickly and will not change or kick down, and revs in neutral limited to 3,000 RPM. When I got back, I restarted the engine to see if it would clear - but it did not, and the "El. Power Control EPC - Visit Workshop!" warning light came onto the display.
So today, I plugged it into my generic OBD2 reader, and read the code: P1408 - EGR System Flow out of KOER Self Test Range.
Thinking it would just be a clogged up EGR valve (the previous owner only did short trips), I removed it today and gave it a good clean (including the mechanism under the black plastic cover, which was actually more clogged than the valve itself), thinking it would solve the issue. However, the fault code persists and re-appears every time the car is started.
When the code is cleared, upon the first start the "EPC" warning isn't there, but the car is still in limp mode. As soon as it is restarted, the EPC warning comes back.
I also just cleaned out the MAF sensor using some brake/clutch spray, which did indeed look pretty dirty - however, it made no change.
My reader also allows viewing of Live Data, including the MAF sensor reading. At a warm idle (~700rpm), the MAF reports around 18 g/s (approx. 2.2lb/min). Does anyone know is this is about right for this car?
Anyone got any experience with similar symptoms, or any suggestions?
Many thanks
Sam
Well, the honeymoon period is definitely over with my new W220. She's a 2005, with the OM648 I6 engine and 140,000 miles.
Coming home from work on Thursday evening, I slowed down from 70mph at a set of traffic lights, and when I went to pull away again, the car was obviously in limp mode - slow acceleration, gearbox goes up through the gears quickly and will not change or kick down, and revs in neutral limited to 3,000 RPM. When I got back, I restarted the engine to see if it would clear - but it did not, and the "El. Power Control EPC - Visit Workshop!" warning light came onto the display.
So today, I plugged it into my generic OBD2 reader, and read the code: P1408 - EGR System Flow out of KOER Self Test Range.
Thinking it would just be a clogged up EGR valve (the previous owner only did short trips), I removed it today and gave it a good clean (including the mechanism under the black plastic cover, which was actually more clogged than the valve itself), thinking it would solve the issue. However, the fault code persists and re-appears every time the car is started.
When the code is cleared, upon the first start the "EPC" warning isn't there, but the car is still in limp mode. As soon as it is restarted, the EPC warning comes back.
I also just cleaned out the MAF sensor using some brake/clutch spray, which did indeed look pretty dirty - however, it made no change.
My reader also allows viewing of Live Data, including the MAF sensor reading. At a warm idle (~700rpm), the MAF reports around 18 g/s (approx. 2.2lb/min). Does anyone know is this is about right for this car?
Anyone got any experience with similar symptoms, or any suggestions?
Many thanks
Sam
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