Hi everyone, bought an used C4S.
i have a Check Engine and it’s P0056 and P0161.
i changed both sensor and still have issues.
any ideas?

 

Did you replace Bank "2" Sensor "2" ??

If so then check to see if Rodents ate your wiring to the sensor......and/or test for 12v power to the sensor , and get the diagram and check the fuse ...

 

Need something like Durometric to read the codes. Chances are you have another problem. I eventually found and intake gasket leak- after that all was great. No codes and it smoged like an electric motor.

 

Thank you. I do have an air leak from my oil filler tube that is craked.
We did check and all the wire is right. I do have a Bank "2" Sensor "2" but we changed both

 

I’m pretty sure those codes are for the oxygen sensor heating, check the wiring…… at the connectors from the car…..

-Eric

 

Do you guys think this can be an ECU issue too?

 

Most likely no. But the wiring to the computer or o2 itself along with the pins in the dme plug could all be an issue. Understanding and diangnostic with a multumeter is the only way to find the issue

 

Anybody used ECU Doctor in FL?
I think of sending my ECU to remove the sensor because i still have this issue

 

I had to screw around with this recently and was able to figure it out. First, make sure your sensors are not installed backwards. Then I would take the plug and check (i think it's a black wire) and ensure you're getting 12v to it. Ignition has to be on. otherwise you'll get a false positive. If that's all good, then take the plug from the sensor side and confirm that you have appropriate resistance between the 2 white wires. That's for the heating element. This is what a reading looked like for me for a working sensor. If you're in the 2-3ohm range then that's a sensor issue. As as other said, check your wiring.

 

They have done a dme health check and repaired my immo. They r a good company and resource.