My 05 cobalt ss/sc keeps resetting the codes for O2 sensor... As far as performance, driving in town at lower speeds it seems to choke some, but if you "get in it" it runs good. P0133 - B1S1, P0172 - Fuel system rich, P1133 - Insufficent switching. I have replaced the O2 sensor with OEM three times and replaced the pigtail with OEM. Any ideas why or what could be causing this? In desperate need of advise!!!

 

Replace the OTHER O2 Sensor (Our cars have two)

 

b1s1 is the one closes to the engine. I think it's in the manifold.

 

I hope you havent been replacing the one on the downpipe, lol

 

B1S1 is the front O2 sensor and it is just in front of the cat, and is not in the manifold. I really don't believe the sensor is bad. It is running too rich, which I replaced the injectors cause I thought one might be leaking. SO I am sure there is something making the O2 not switch correctly.

 

My car thew a forward O2 sensor code (forgot what one) and it stayed after replacing it. I disconnected my aft (Downpipe) sensor and the code went away (Aft sensor is deleted)