P0421 Diagnostic Trouble Code Discussion for June 2006
Warmup Catalyst Efficiency Low (Bank 1)
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| Help Request | Posted | |
| 2000 Volkswagen Passat GLS 2.8L MIL Lamp on VIN: WVWTH23BOY P0421: Catalyst efficency Bank 1. Ok trying to help out family members car with MIL on for OBII test. I am a RI emissions facility. This car is registered in Mass. Both banks for cat efficency codes come up. However the car runs perfect and has near zero emissions so obviously the cats are doi... |
June 26, 2006 |
