P0420 Diagnostic Trouble Code Discussion for October 2013
Catalyst Efficiency Below Normal (Bank 1)
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| Help Request | Posted | |
| 2007 Chevrolet Silverado 1500 LTZ 5.3L MIL Lamp on VIN: 3GCEK13M27 P0420: Catalyst System Low Efficiency (Bank 1). ... p0420.they changed cat assy. code came back on.I got veichle with p0420 & p0430.cats tested cold.o2's switching/following fronts.checked,tune-up new.no vac.leaks,no exhaust leaks,02's in correct positions.f/press,ok.holds pressure.stft and long term fu... |
October 07, 2013 |
