P0430high severityPowertrain
Catalyst System Efficiency Below Threshold Bank 2
on 2002 BMW M3 3.2L I6 S54 · RWD
What this code means
The Bank 2 catalytic converter is not performing efficiently. Same as P0420 but for Bank 2.
Symptoms
- Check Engine Light
- Failed emissions test
- Possible sulfur smell
Common causes
- Worn catalytic converter
- Exhaust leak near downstream O2
- Faulty O2 sensor Bank 2
- Misfire damage to catalyst
- Oil contamination
Diagnostic steps
- Compare upstream/downstream O2 waveforms Bank 2
- Check for exhaust leaks
- Test downstream O2 sensor Bank 2
- Check for misfire codes
- Inspect for oil consumption
Repair notes
Same approach as P0420 but for Bank 2. Replace catalyst if confirmed failed.
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Other Powertrain codes on this vehicle
29CC
Misfire Cylinder 1
29CD
Misfire Cylinder 2
29CE
Misfire Cylinder 3
29CF
Misfire Cylinder 4
29D0
Misfire Cylinder 5
29D1
Misfire Cylinder 6
29D2
Misfire Cylinder 7
29E0
Lambda Additive/Idle Adaptation Limit, Bank 1
29E1
Lambda Additive/Idle Adaptation Limit, Bank 2
29E2
Lambda Multiplicative Part-Load Adaptation Limit, Bank 1