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P0420 Diagnostic Trouble Code Discussion for October 2004

Catalyst Efficiency Below Normal (Bank 1)

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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
1999 Chevrolet Silverado 1500 4.3L MIL Lamp on VIN: 1GCEC14WXX
P0420: Catalyst System Low Efficiency (Bank 1). I have a Ho2 nightmare and I hope some one has seen this before. I have used two different scanners and still get the same readings, sensor 1-1 and 2-1 vary with good cross counts and steady pulse width readings on both banks.Sensor 1-2 shows roughly 650 to 80...
October 12, 2004
2001 Volkswagen Beetle GL 2.0L no throttle VIN: 3VWCB21CO1
P0420: Catalyst efficiency. ... under vehicle. After cat. sensor wires all were bare. Before cat. sensor wiring appeared okay. Put car back on the ground and now I have no throttle response. Originally I only had the P0420 CODE. Since then I have the other four codes. I've run the thrott...
October 13, 2004
2002 Volkswagen Golf GLS 2.0L MIL Lamp on VIN: 9BWGB61J72
P0420: Catalyst problem bank 1. ... an intermittant p0420 catalyst code. We have replaced both oxygen sensors with VW parts. The catalytic converter is 100 degrees hotter at the rear (so it's obviously working). We can force the vehicle to do a catalyst readiness monitor test with our Baum s...
October 26, 2004