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P0431 Diagnostic Trouble Code Discussion for February 2013

Warmup Catalyst System Efficiency Low (Bank 2)


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Trouble Ticket Help Requests for DTC P0431
Help Request Posted
2003 Audi A6 Quattro Avant 3.0L Misfire VIN: WAUVT64B43
P0431: Cat Bank 2 Efficiency Below Threshold. This Audi originally came in for a misfire, smoking and running rough. We replaced the vacuum valve for the crankcase vent system (diaphragm ruptured) and cured the lean condition, smoking and rough idle. Car was left with a misfire cold on cylinder 1. Replaci...
February 12, 2013