P0422
Main Catalyst Efficiency Below Threshold Bank
Generic code
Auxiliary Emissions Control
Medium severity
Moderate repair
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What P0422 means
- The fault code P0422 indicates that the catalytic converter in Bank 1 is not working efficiently and has fallen below the required threshold. This may cause an increase in harmful emissions or even failure to pass an emissions test.
Possible symptoms
- Illuminated check engine light
- Failed emissions test
- Decreased fuel efficiency
- Poor engine performance or acceleration
Possible causes
- Damaged or failed catalytic converter
- Faulty oxygen sensor
- Exhaust leaks
- Engine misfires or running rich
- Failed engine control module (ECM)
Related parts
- Catalytic Converter: A catalytic converter is a device that converts toxic gases and pollutants to less harmful pollutants. Problems lead to harmful emissions out of limit, rotten egg smell from exhaust & reduced speed
Possible solutions
- Replace the catalytic converter
- Replace or repair the faulty oxygen sensor
- Repair any leaks in the exhaust system
- Address any engine misfires or running rich issues
- Replace the engine control module (ECM) if necessary
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P0422 on OBD DashX
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