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P0420 Diagnostic Trouble Code Discussion for January 2012

Catalyst Efficiency Below Normal (Bank 1)

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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2004 Volkswagen Jetta GLS 2.0L MIL Lamp on VIN: 3VWSA69M04
P0420: cat efficiency bank 1. car is in now for a check engine lite on,timing belt and other p.m.maintenance before i start i would like to know if any vw techs seen these codes all together or if they have anything in common.alldata has no tests for po333,po328,po1326 any help would be gr...
January 10, 2012
2006 Chevrolet Aveo LS 1.6L MIL Lamp on VIN: KL1TD56646
P0420: Catalyst System Low Efficiency. ... car lot with a check engine light on. P0420 in system. It also had a few air bag codes. Reseating a connector and clearing the codes made the air bag light go away. Usually I can monitor the rear O2 to see if it is mirroring the front but this one is a l...
January 20, 2012
2003 Toyota Highlander 3.0L MIL Lamp on VIN: JTEHF21A33
P0420: Catalyst Efficiency Below Normal (Bank 1). This vehicle has 2 catalytic converters at the manifolds and 1 before the front muffler. 1 air fuel sensor before each front converter and only 1 downstream oxygen sensor after the rear converter. So how are we monitoring cat 1&2? Or is the downstream cons...
January 27, 2012