2012 E350 (W212, M276) -
Out Of Control!!
Joined: Apr 2019
Posts: 12,003
Likes: 6,827
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
I replaced all four cps with genuine bremi and delphi (had ordered ebay ones before) and that has fixed all timing correlated codes. The car has been driving and starting smoothly since. However, I got a new CEL this time on a recent drive for p0137 bank 1 sensor 2 o2 sensor circuit low. I cleaned the ecu plug (little residual saturation from old cps) and the code came back. I will check and clean the o2 sensor plug next but at this point not sure what the actual solution will be to this harness. I replaced this specific o2 sensor about 10000 miles ago for an unrelated issue.
is your exhaust sensor from a trusted source or from eBay?
You may be able to come up with a O2 "pigtail" to spate expensive sensors.
Thread Starter
Newbie
Joined: Mar 2025
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2015 CLA45 AMG, 2012 E350
I found oil at the connector. I cleaned it on the male and female side but the CEL came on for p2270 (too lean condition) and p0137. I checked the voltage at operating temp for that sensor and its 0V. I did smoke test the intake and found no air leaks. Im going to get a new o2 sensor but I don't want to have to keep replacing it if oil is still in the harness so unsure if I should leave the old sensor in with the CEL and wait a few weeks to keep cleaning the connector or just put the new o2 sensor in from FCPEuro and warranty it.
Out Of Control!!
Joined: Apr 2019
Posts: 12,003
Likes: 6,827
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
I found oil at the connector. I cleaned it on the male and female side but the CEL came on for p2270 (too lean condition) and p0137. I checked the voltage at operating temp for that sensor and its 0V. I did smoke test the intake and found no air leaks. Im going to get a new o2 sensor but I don't want to have to keep replacing it if oil is still in the harness so unsure if I should leave the old sensor in with the CEL and wait a few weeks to keep cleaning the connector or just put the new o2 sensor in from FCPEuro and warranty it.
That's why dealer replace engine harness.
you may get some relief with lambda pigtail if you can locate a match.
MBWorld God!
Joined: Dec 2019
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