P0430 code. Check my logic

[k9sar]

So the new(to me) pathy is periodically throwing a P0430 code which indicates an inefficiency in the catalyst system bank 2. I have read that a bad O2 sensor can cause this but I would expect an O2 sensor code if that were the case. I'd rather check this first before replacing the front DS cat. So here's my diagnostic logic..

 

I should be able to remove the O2 sensor from behind the DS cat and swap it to the other side (PS). Not sure how the wiring is but I would think there is a plug or something that I can disconnect that will allow me to swap the sensors but leave the wiring intact (as if I were replacing the O2 sensors). I'll reset the codes and let the wife drive it for another few weeks to see if a code returns.

 

one of the following should tell me my next step(s):

 

1. P0430 returns - must be a bad CAT or bad O2 sensor harness wire since it remained on bank 2. visually/electrically check wire and probably replace cat.

2. P04xx throws indicating inefficiency on Bank 1. This would say my O2 sensor is bad

3. No codes - must have been a bad connection or something that got resolved when I swapped the sensors.

 

Sound like reasonable logic?

[Slartibartfast]

If the wiring will reach, it sounds reasonable to me.

[byob]

A failed 02 sensor would be a stretch. Two possible failures are more likely the failed cat or an ecm update. If you have a scanner I would read the line graphs of both cats