[Black Gold]

Car threw these codes recently, have a visit with the dealer next week. No aftermarket downpipes on the car.

P0031
P0051
P0037
P0057
P2C9C
P2C9D
P2C9E
P2C9F

I believe the bottom 4 are o2 sensor codes....but any feedback will help so I know what to expect. Car has ses light in yellow, dealer visit scheduled for Monday.

Thanks guys

[135Pats]

Those could well be O2 codes, FWIW when my precat lambda O2 took a bath a few months back my car threw P2CAB and P2CA7, along with the SES light.

[Black Gold]

Thanks. Yea I just don't know what the first few codes are.

Did new sensors fix your issues?

[135Pats]

Originally Posted by KennyPowers

Thanks. Yea I just don't know what the first few codes are.

Did new sensors fix your issues?

Long story short: yes.

Extended version: The car was suffering from a crappy cold start and jumpy idle, I didn’t drive it for more than a few days in this condition, but it deteriorated and by the time I took the car in, it absolutely wanted to quit on me on that morning’s cold start. Once the car was warm it drove somewhere in the ballpark of “normal”. I took it in with the codes and the dealer tried to tell me something along the lines of “your DCI is messing with AFRs” to which I gave a serious stink face and asked them to please look at the precat O2. Shockingly, the O2 had failed just as the codes had shown, and it was replaced under CPO for free. I never looked at the O2 myself, so I’m not sure what the problem was. The issue cropped up after swapping midpipes, so maybe the downpipes got bumped or jostled at some point and that caused damage to the sensor? Not sure to be honest.

[Black Gold]

Wow. Well at least you got it sorted out

In my case, there is no deterioration of idle or drivability. Does seen like the car is a bit more sluggish, but could be due to cel. I am not driving the car hard whatsoever until I see the dealer

Any feedback on the first codes is helpful

[Black Gold]

So it looks like all 8 codes are o2 sensor related.

The first four are "heater control circuit" codes which are related to a heat / voltage monitoring device in the o2 sensors.