PO420 Exhaust Code?

Originally Posted by bripolar66

i put z1 test pipes on at work yesterday, drove home and went right back (on my day off) to work and put my cats back on. test pipes sound like poo. i wish i knew that. my fault for not looking further into it. no SES light tho.

i reccomend to get your a/f ratio checked if u dont have some sort of monitoring system already which most of u probably do about 50 miles after test pipes installed. go to nissan and get a tech to drive with you with the cunsult 3 to check your alphas. mine was rich as hell, it may have changed if i kept them on longer. they really did sound awful. i was pissed.