Need help o2 sensor
 

I changed out my cats for test pipes the other day. Now I'm getting codes p1148 and p0031. It says it's on bank 1 sensor 1. I just need to know what side it's on and if it's the one in the test pipe or header. Thanks in advance.

Sensor 1 is the upstream sensor before the catalytic converter; are you sure you hooked everything up properly? P1148 is a short or issue with the O2 sensor wiring. Make sure you don't have any significant leaks from the header to test pipe connection either.

So what side would that be on? Because on the passenger side had to drill out one the holes. So maybe I clipped one of the wires on the sensor something.