2002 Lancer OZ - Check Engine Light, P0421 Trouble Code

Oct 27, 2003 3 Replies

We recently purchased a '02 Lancer OZ and the check engine light came on. The only trouble code that the computer reports is:



P0421 - Warm Up Catalyst Efficiency Below Threshold (Bank 1).



The car is no longer under the bumper to bumper warranty (has 37k miles), so I want to avoid the dealer if possible. Does anybody have any idea as to what the problem could be? The car runs smooth, so there is nothing visibly wrong with the way it runs. Thanks in advance for any insight to my problem.


The catalyst is part of the emmissions and those have a longer warranty that is mandated by the Federal Gov't. It should still be under warranty. Go get it checked out!

DragonRider wrote in news: snipped-for-privacy@4ax.com:

5 years on emissions last I knew. Had this fluid leak in 2001 on a 96 Mitsu. Took it in. Labeled as front inner knuckle axle seal. Apparently this item considered a pollution issue. Beat in-service date by 2 months. Got a bill with n/c.

Depends also from state to state. Some states have longer requirements than others. Your milage may vary. All thoughts are opinions only and not representive of actual fact. Tax, Tag, Title, and fee's extra.

It's been a long day.

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