Fault Code P2031 come back on after Upstream O2 (Lambda) sensor replacement.
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C200K Coupe
Fault Code P2031 come back on after Upstream O2 (Lambda) sensor replacement.
Hi there all.
Got a C200K Coupe with a M111 engine. It previously had an engine light on which had the same fault code as well as a MAF sensor fault. Replaced both and the O2 sensor fault has come back. Didn't see any oil in the loom (as a few forums have suggested).
Wondering if you recon it could be a dud sensor?
Got a C200K Coupe with a M111 engine. It previously had an engine light on which had the same fault code as well as a MAF sensor fault. Replaced both and the O2 sensor fault has come back. Didn't see any oil in the loom (as a few forums have suggested).
Wondering if you recon it could be a dud sensor?
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C200K Coupe
No, after market. Brand is Vemo. Got it from a trusted euro parts supplier i have worked with before.
Strange thing is, after much searching, this fault should relate to post cat sensor (dowmstream), but the scanner said upstream (pre cat)?
I'm honestly confused.
Strange thing is, after much searching, this fault should relate to post cat sensor (dowmstream), but the scanner said upstream (pre cat)?
I'm honestly confused.
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C200K Coupe
To be honest, i am doing the diagnosis. I have around 5 years on the tools MB experience however, i have now been off the tools and in other industries for the past 15 years. The scan was done on a Snap-On UBDII scanner from an indy garage near my work.
The supplier is one of the main wholesale aftermarket euro parts suppliers in Melbourne (i am not willing to name them in this context), i have a a great deal of experience with them from my time in a previouse job and i DO trust them.
What is confusing me is that the scan text identifies the "Upstream" O2 sensor however, the code itself points to the "Downstream".
I honestly cannot afford to have a tech with current MB experience look at it.
The supplier is one of the main wholesale aftermarket euro parts suppliers in Melbourne (i am not willing to name them in this context), i have a a great deal of experience with them from my time in a previouse job and i DO trust them.
What is confusing me is that the scan text identifies the "Upstream" O2 sensor however, the code itself points to the "Downstream".
I honestly cannot afford to have a tech with current MB experience look at it.
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Joined: Feb 2016
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From: Cincinnati, Ohio
mb, saab, acura, dodge
Your snappy scanner should read all the parameters. I've never seen that code in connection with upstream sensor. I hook up my scanner and read the O2 sensors output at 2500 rpm. Compare the up streams to each other and down streams to each other. Usually you can figure out if a sensor is sporratic or if you have a vacuum leak or some other problem.
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C200K Coupe
Thanks for that. I actually got some local advice as well both from an MB indy specialist and my former workplace (an independent euro workshop) and was told to check the plug at the intake Cam Advance solenoid for oil contamination. Sure enough, it was soaked.
Imparts in Aus have these available at a good price and i have been told to change the downstream sensor as well. Once done, clean the loom and clear the fault and all should be peaches.
I will update thise once i have made these repairs with an outcome.
Imparts in Aus have these available at a good price and i have been told to change the downstream sensor as well. Once done, clean the loom and clear the fault and all should be peaches.
I will update thise once i have made these repairs with an outcome.
