RPB

So I just got my C36 back yesterday, new water pump and thermo... He also swapped my spark plugs for me and told me the harness is getting brittle, so he tried to be very careful when changing them. Car runs great! My check engine light has been on w/ code P0400 for EGR for a few weeks, will address this soon. Today I pulled two codes, one for existing EGR but now one for o2 sensor. I just replaced both about 3k miles ago. To make a long story short after doing some searching or maybe too much of it I am reading that oil can travel down a bad harness. Is this likely my problem or just a fluke o2 code, I reset them and am waiting for recurrence. Heard the issue can also plague the ECU!?! Love my 36, she get what she needs in the end.

Any ideas?

jayrasheed

if the wiring is cracking down thats ur main reason for faults
on my AMG36 i had to change the engine harness wires, the harness going to the gearbox, the wiring inside the ETC. and now the car runs with zero faults.

RPB

Well I know my EGR code is correct, my tubing needs to be replaced and the only other code if for my pre-cat o2 that was recently replaced. Car runs fine. Just was shocked when I heard oil can run through the harness damaging other components and do not want that!!

Jasssc

Same thing happened to me. My egr code came first then about two weeks later my o2 sensors came around.
My only guess is that the egr somehow messes with the o2 sensors if it goes bad, but I'm not sure. I just know I will get them fixed as soon as I can because I'm sure I'm losing some power with them being bad