code 0420 hc in pcm please help please ?
Thread Starter
Supporting Vendor
Joined: Oct 2002
Posts: 50,281
Likes: 518
From: Cleveland OH
St. Jude Donor '11,'13
code 0420 hc in pcm please help please ?
states catylist low efficinecy bank one . any idea i have sw headers with pre gutted cats. i think the rear cats are fried. will this hurt my performance. all input will be greatlly appreciated since the tunner and the tunnie cant give me a straight answer :confused: the rear cats are stock
Instructor
Joined: Oct 2001
Posts: 249
Likes: 0
From: Mesa AZ
Re: code 0420 hc in pcm please help please ? (stunna)
The rear cats could be going out on your car. It is also possible (on 02+) cars that it is the sensitivity of the computer. I have seen this on a few newer cars, but rarely on the pre 02 cars. It should not hurt performance unless they are clogged, which shouldn't happen. If they are blowing (burning) out, you should notice a fine metallic flake coming out of the back, possibly on the rear fascia.
Mike
Mike
Thread Starter
Supporting Vendor
Joined: Oct 2002
Posts: 50,281
Likes: 518
From: Cleveland OH
St. Jude Donor '11,'13
Re: code 0420 hc in pcm please help please ? (mike@xtreme)
mike, thanks for your help. the car is a 2000 and i have had the headers for 2 yrs and now all the sudden its giving me a problem with check engine. i might give you a call to talk if you have a moment :cheers:
