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P0431 Diagnostic Trouble Code Discussion for September 2006

Warmup Catalyst System Efficiency Low (Bank 2)

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Trouble Ticket Help Requests for DTC P0431
Help Request Posted
2000 Mazda MPV DX 2.5L MIL Lamp on VIN: JM3LW28G3Y
P0431: Warmup Catalyst Efficiency Below Normal (Bank 2). This Mazda is back with the same codes. All scan data looks normal except for post warm up cat sensor activity. A search of the archives shows that some Mazda's had a re-flash for these codes, but none seem to be available for this one. No TSB's listed in Alld...
September 10, 2006
2000 Audi A4 2.8L MIL Lamp on VIN: WAUDH28DOY
P0431: right bank warmup cat below efficiency. We have four scan tools in the shop and cannot monitor both oxygen sensors to test cat, efficiency. I suspect that both cats are bad but hesitate to replace them and have a repeat failure. Does anyone have advice about what the cause might be or is this a comm...
September 13, 2006