I keep throwing the engine code P0136 O2Sensor Circuit Malfunction (Bank 1 Sensor 2) It will go on for a day then off for 2 and its been doing this for 2 weeks now. I need to help understanding whats going on and what is really wrong with my car....if anyone can help me that would be awesome thanks!

 

my car use to do that right after getting v42 update about 3yrs ago.
dealer looked at it, 02 sensor was fine.

i just monitored the situation... one day i changed oil and drove it
around... no issues since. not sure if the old oil that was in the engine
has anything to do with it but might be worth a try if your coming close
to your scheduled maintenance. i think it was just coincidence, but
who knows.

otherwise, as the DTC shows, bad 02 sensor.

 

thanks man...i just wonder if i have a bad O2 which one it is....

 

i had the same thing, and it went away after a couple of weeks

IIRC it's the sensor downstream of the cat

 

I have had an almost permanent Service Engine light since the car was new. One new cylinder head and numerous sensors later it is back. The OBD reader shows no fault (zero code). Anyone any ideas?

 

is the one after the cat.

Check engine light with no stored code? That's an ECU fault.... If there's no code, then there's no light.

Matt