P0420 Diagnostic Trouble Code Discussion for February 2018
Catalyst Efficiency Below Normal (Bank 1)
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| Help Request | Posted | |
| 1999 Chevrolet Astro 4.3L No Start, Poor Idle Quality, Stall VIN: 1GCDM19W9X P0420: Catalyst System Low Efficiency (Bank 1). This thing wont idle. If you give it any throttle at all it runs fine.It can be kept running at even as low as 600 rpm by leaning on the throttle. No throttle, no run. Of course the first thing I did was throw an Idle Air Motor at it, no joy. No codes exce... |
February 06, 2018 | |
| 2009 Dodge Grand Caravan SE 3.3L MIL Lamp on VIN: 1D8HN44E79 P0420: cat eff low bank 1. I am stumped at this vehicle which should be an easy diagnose. Vehicle came in last December for po420. The vehicle had no running issue. No other codes. Checked exhaust system for leaks-none found. 150,000 mileson vehicle. Replaced converter with an after... |
February 06, 2018 | |
| 2009 Dodge Grand Caravan SE 3.3L MIL Lamp on VIN: 1D8HN44E79 P0420: cat eff low bank 1. I am stumped at this vehicle which should be an easy diagnose. Vehicle came in last December for po420. The vehicle had no running issue. No other codes. Checked exhaust system for leaks-none found. 150,000 mileson vehicle. Replaced converter with an after... |
February 07, 2018 | |
| 2009 Cadillac Escalade Hybrid 6.0L MIL Lamp on VIN: 1GYFK43559 P0420: Bank 1 cat efficiency. Thanks for help on this hybrid escalade, it sets faults for both cats, they were just replaced at another shop with aftermarket parts. The upstream o2 sensors switch normally, the down stream stay around 725 - 800 mv while driving. On a hard decell they will g... |
February 26, 2018 |
