P0421 O2 sensor extension harm the vehicle?
10-04-2016, 07:29 AM
#1
Audiworld Junior Member
Thread Starter
Join Date: Jul 2016
Posts: 49
Likes: 0
Received 0 Likes
on
0 Posts
P0421 O2 sensor extension harm the vehicle?
So I have the po421 code. I am thinking of adding the o2 sensor extension after the cat. Does this code mean my cat is clogged or just not working properly? We do not have emissions tests in Montana so I am not worried about that. I am worried if this could harm the vehicle at all.
10-10-2016, 06:37 AM
#2
AudiWorld Member
Join Date: Jan 2008
Posts: 411
Likes: 0
Received 0 Likes
on
0 Posts
Hole in the flex section before the cathalyst
Almost 100 percent sure that you have a hole in the flex section. Most people change out the entire down pipe and conclude it was the cathalyst. If you decide to do that it will work. I've done it before just because it is less work and didn't have a welder. Rock auto has the setup for about $310 per side... there are diy's for it too...
Thread
Thread Starter
Forum
Replies
Last Post