2009 galant p0431 again!
Hi I’m hoping to get some advice on what to do next.I have a 2009 Galant with code p0431 and p0421. I have replaced the catalytic converter with an aftermarket and all O2 with OEM Denso sensors . As I road tested the check engine light came on and the codes are the same. Is it possible I did something wrong? Any advice is appreciated.
Thread
Thread Starter
Forum
Replies
Last Post



