P0420 Diagnostic Trouble Code Discussion for March 2016
Catalyst Efficiency Below Normal (Bank 1)
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| Help Request | Posted | |
| 2003 Porsche 911 Carrera 3.6L MIL Lamp on VIN: WP0BA29953 P0420: Bank 1 CAT efficiency. Hi this one was brought to me from a Dodge dealer that sold this Porsche on the used car lot. Both CAT's are producing efficiency codes and they replaced both CAT's and all 4 02 sensors, with OEM parts. Looking at the Data the 02's are switching ok. Can a mixt... |
March 17, 2016 | |
| 2002 Pontiac Grand Prix SE 3.1L Hesitation, MIL Lamp on VIN: 1G2WK52J42 P0420: Catalyst System Bank 1 Low Efficiency. Car starts right up, idles fine. However when driven stumbles / hesitates / lack of power under load. Plugs and wires were original. Plugs in bad shape. Replaced spark plugs and wires. Symptoms seemed to improve slightly. Fuel pressure was good and increased a... |
March 23, 2016 |
