P0420 Diagnostic Trouble Code Discussion for July 2017
Catalyst Efficiency Below Normal (Bank 1)
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| Help Request | Posted | |
| 2008 GMC Sierra 1500 WT 5.3L MIL Lamp on VIN: 1GTEC19J68 P0420: catalyst efficiency low bank 1. ... idle and a code P0420. We scanned the 02 sensors and although bank 1 o2 sensor had many oscillations compared to bank 2 but the amplitude was low. We ran injector cleaner in it which smoothed out the idle and it ran normally. We replaced the catalytic conv... |
July 07, 2017 | |
| 2008 GMC Sierra 1500 WT 5.3L MIL Lamp on VIN: 1GTEC19J68 P0420: catalyst efficiency low bank 1. ... idle and a code P0420. We scanned the 02 sensors and although bank 1 o2 sensor had many oscillations compared to bank 2 but the amplitude was low. We ran injector cleaner in it which smoothed out the idle and it ran normally. We replaced the catalytic conv... |
July 11, 2017 |
