Gonna go ahead and throw this out there po134 code

[95camaroZNC]

I installed my longtubes and ran the car for a while open headers (30 miles at most) everything was fine until a shop here in town installed my x pipe, now i think they may have messed up the driver side o2 sensor. It was a old one out of the pipe in the front, i used extensions on the sensors.I felt taped up the extensions just in case they would get too hot and melt/fry when i installed the headers. Im going to try swapping one of the other o2 sensors i have into the drivers side and see if that corrects it. The extensions came with my flowtech headers still brand new in the package so i dont really think they could be the problem. Any input would be helpful. Im thinking its the drivers side o2 because the passanger side one is brand new, we stripped one of my front ones pulling them off so bought a new one.

Thanks alot!

[peterlawl84]

It could be your extensions too. I kept having issues when I initially installed my LTs with extensions. Finally got the longer ones (13111) and haven't had issues since.
Most people will agree that it is better to just get the longer ones and not use extensions.

[95camaroZNC]

It was just the driveside o2 sensor, its fixed now though. Thanks!