o2 sensor throws code after putting on cats

[andystang]

i just replaced my off-road x pipe with the stocker and both o2 sensors threw a code after i started it. they were fine before and one of them even was replaced under a year before! any idea what would cause this?

 

[brentwoodboy]

Did you reset the computer after you put em on?

Disconnect the batt. for like 30 mins or so, reconnect, then see. Also, during installation/deinstallation you could have broke them (maybe), they are kinda fragile.

 

[andystang]

im pretty sure i didnt break them i erased the codes and put a new one in one side, and it still is coming up with one code for bank 2. which bank is which side?

 

[bjl95mustang]

Did you touch the sensor ends of the o2's with your bare hands? Try taking them off and using a propane torch to clean them. Just heat them up and burn any thing off of them.