98 Gen 2.5 CEL Code P0421

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98 Gen 2.5 CEL Code P0421 #1042018 02/15/12 03:11 AM

Joined: Feb 2008

Posts: 120

Phoenix, AZ

OneTime

Wheeler

I have a CEL light on with a code P0421. I remember the dealer telling me a while back it was either the #1 or the #2cat, I cant remember which. I pulled the code again at autozone and was given the P0421 "warm up catalyst effeciency below threshhold" Do I simply need to replace one of the cats or is something else going on?

98 Gen 2.5 w/ winter package & 31x10 BFG ATs.

Entire Thread
Subject	Posted By	Posted
98 Gen 2.5 CEL Code P0421	OneTime	02/15/12 03:11 AM
Re: 98 Gen 2.5 CEL Code P0421	fasteddy	02/15/12 05:09 AM
Re: 98 Gen 2.5 CEL Code P0421	OneTime	02/17/12 05:04 AM
Re: 98 Gen 2.5 CEL Code P0421	JohnnyBfromPeoria	02/17/12 06:14 PM
Re: 98 Gen 2.5 CEL Code P0421	OneTime	02/17/12 07:46 PM
Re: 98 Gen 2.5 CEL Code P0421	fasteddy	02/18/12 04:36 AM

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