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P0421 Diagnostic Trouble Code Discussion for October 2012

Warmup Catalyst Efficiency Low (Bank 1)


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Trouble Ticket Help Requests for DTC P0421
Help Request Posted
2001 Volkswagen Passat GLX 2.8L Surge, Cuts out VIN: WVWBH63B01
... Never straight or left. We do not currently possess a VW factory scan tool. The exhaust repair will most likely solve the P0421,P0431, and P1176 codes (unless cat is damaged), o...
October 29, 2012
2001 Volkswagen Passat GLX 2.8L Surge, Cuts out VIN: WVWBH63B01
... turning right while accelerating. Never straight or left. We do not currently possess a VW factory scan tool. The exhaust repair will most likely solve the P0421,P0431, and P1176 codes (unless cat is damaged), our question is mainl...
October 29, 2012