P0420 Diagnostic Trouble Code Discussion for November 2025
Catalyst Efficiency Below Normal (Bank 1)
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| Help Request | Posted | |
| 2015 Chevrolet Trax LT 1.4L MIL Lamp on VIN: KL7CJLSB4F P0420: . CODE P0420, This has been a 2 month wrestling match. After confirming with dealer that it's Fed Emmissions we replaced catalytic converter twice. Once Walker Fed and Once Walker Calif. Replaced flex pipe, oem oxygen sensors and exhaust manifold. Called in ... |
November 03, 2025 |
