P0421 Diagnostic Trouble Code Discussion for December 2004
Warmup Catalyst Efficiency Low (Bank 1)
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| 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 |
