I have a 2002 civic ex 1.7, has a new aftermarket exhaust and cat with new o2s that place the cat below the car. I belive the cat was off the header originally. Anyway I have a po132 code for bank 1. Should I try a new o2 or run a defowler? Is the first o2 is looking for a signal with the cat and now the cat is on the second 02.