I replaced my stock midpipe a few days ago from a offroad h pipe because of emissions. But last night my rear o2 sensor bank 2 engine service light came on. What could cause this even when i replaced the stock midpipe? Could running a offroad H pipe mess up my o2 sensors?
Thanks, car is a 01 gt.

 

Your o2 sensors may be dirty / need to be replaced.

 

I'm not sure what's going on now. The light turned off by itself this morning. I didn't think it was possible for the light to turn off without clearing it. Is it possible it could have fixed it self?

 

It will probably come back on but who knows.. My car takes a good 200 miles of driving before the rear o2 sensors cycle through their tests.