P0420 Diagnostic Trouble Code Discussion for January 2015
Catalyst Efficiency Below Normal (Bank 1)
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| Help Request | Posted | |
| 2005 Buick Rendezvous CXL 3.4L MIL Lamp on VIN: 3G5DB03E45 P0420: Catalyst System Low Efficiency. ... rendevous that keeps setting the infamous P0420. We had this vehicle in before and I had replaced the cat converter (only has one, shared with both banks)Rear HO2S mirrors primary sensor just like it did before. It was fine after I initially replaced the c... |
January 14, 2015 | |
| 2006 Cadillac DTS 4.6L MIL Lamp on VIN: 1G6KD57Y76 P0420: Catalyst System Low Efficiency (Bank 1). Car came in with code P0420. Converter tested marginal so I replaced cat with a Walker Ultra and updated the computer with the latest software for false code P0420 setting. Ran bay test to run monitor and passed. Road tested vehicle while watching oxygen senso... |
January 17, 2015 |
