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P0421 Diagnostic Trouble Code Discussion for August 2007

Warmup Catalyst Efficiency Low (Bank 1)

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Trouble Ticket Help Requests for DTC P0421
Help Request Posted
2000 Volkswagen Passat GLS 2.8L MIL Lamp on VIN: WVWMD23BXY
P0421: cat warm up effiency bank 1. have a vehicle in here have replaced o2s and still popping with this code . any help would be great . looked at o2s and the cat seems to be lighting off just fine . any body had this issue ? is this a common problem ?
August 21, 2007