Common Symptoms
- Check Engine Light illuminated
- Slight decrease in fuel economy
- Vehicle runs normally with no driveability issues
- May fail emissions inspection
- Catalytic converter does not reach normal operating temperature
Most Likely Root Causes
- Faulty catalytic converter with degraded substrate on bank 2
- Malfunctioning oxygen sensor providing incorrect readings
- Exhaust leak upstream of catalytic converter
- Failed catalytic converter temperature sensor
- Engine running too cool due to thermostat stuck open
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Component Location
The bank 2 catalytic converter is located in the exhaust system on the side of the engine opposite cylinder number one.
Manufacturer Notes
Some manufacturers use post-catalyst temperature sensors while others calculate catalyst temperature based on oxygen sensor data and operating conditions.
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