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P0421 Diagnostic Trouble Code Discussion for December 2004

Warmup Catalyst Efficiency Low (Bank 1)


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Trouble Ticket Help Requests for DTC P0421
Help Request Posted
2000 Audi A4 Quattro 2.8L cat problem VIN: WAUDH68D1Y
P0421: cat efficiency bank 1. 2 codes present p0421 cat efficiency bank 1 and p043 cat efficiency bank 2. codes return about 3 month's after clearing codes. car runs fine. no complaints. is it possible that both cats are bad after only 68,000 miles.
December 16, 2004
2000 Audi A4 Quattro 2.8L cat problem VIN: WAUDH68D1Y
P0421: cat efficiency bank 1. 2 codes present p0421 cat efficiency bank 1 and p043 cat efficiency bank 2. codes return about 3 month's after clearing codes. car runs fine. no complaints. is it possible that both cats are bad after only 68,000 miles.
December 16, 2004