CLK 55 - getting P0151 and P0131 DTC and 0mV readings
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From: Gdansk, Poland
CLK 55 AMG W209
CLK 55 - getting P0151 and P0131 DTC and 0mV readings
Hi there,
I have a pretty strange problem with my CLK. So to be precise - it started with P0151 error code, also rough idling. I started diagnosing and saw that Bank 1 Upstream O2 sensor gives reading jumping 0-3500mV, which is way too low and too high. I checked the connections - everything looked fine, so cleaned them up and proceeded with diagnosing. No change. Next step was to swap Bank 1 O2 sensor connector with Bank 2. Same situation. Still readings were like 0-3500mV on Bank 1 (yes, even with connectors swapped).
The next day I got P0131 AND P0151. Readings were 0. I didn't have much time so car was out of use for another week. Today I checked O2 sensor from bank 1 on the table and it was shot, so I replaced it with new NTK O2 Sensor.
Fired up the car, cleared DTC, and I was already happy. About 20 minutes later check engine appeared - again P0131 and P0151.
Live readings on bank 2 are 0, and on bank 1 are like 45-60mV almost stable.
What next should I do? I'm close to check wire by wire from ECU to O2 connectors, but I saw some topics saying it can be MAF problem. I partly checked intake for leaks and didn't find any yet.
Recently done valve cover gaskets and all breather hoses, spark plugs new and all coils checked. Also no exhaust leaks detected. Downstream sensor work fine and the readings are correct. Everything near ECU looks dry and fine.
Thanks in advance for any suggestions!
I use TEXA and Launch for diagnosis.
I have a pretty strange problem with my CLK. So to be precise - it started with P0151 error code, also rough idling. I started diagnosing and saw that Bank 1 Upstream O2 sensor gives reading jumping 0-3500mV, which is way too low and too high. I checked the connections - everything looked fine, so cleaned them up and proceeded with diagnosing. No change. Next step was to swap Bank 1 O2 sensor connector with Bank 2. Same situation. Still readings were like 0-3500mV on Bank 1 (yes, even with connectors swapped).
The next day I got P0131 AND P0151. Readings were 0. I didn't have much time so car was out of use for another week. Today I checked O2 sensor from bank 1 on the table and it was shot, so I replaced it with new NTK O2 Sensor.
Fired up the car, cleared DTC, and I was already happy. About 20 minutes later check engine appeared - again P0131 and P0151.
Live readings on bank 2 are 0, and on bank 1 are like 45-60mV almost stable.
What next should I do? I'm close to check wire by wire from ECU to O2 connectors, but I saw some topics saying it can be MAF problem. I partly checked intake for leaks and didn't find any yet.
Recently done valve cover gaskets and all breather hoses, spark plugs new and all coils checked. Also no exhaust leaks detected. Downstream sensor work fine and the readings are correct. Everything near ECU looks dry and fine.
Thanks in advance for any suggestions!
I use TEXA and Launch for diagnosis.
