Engine and gearbox (P)
P0430: Catalyst efficiency low bank 2
The catalytic converter on bank 2 is not working as well as it should. This can lead to higher emissions and may affect engine performance.
Checked by a licensed car technician · last reviewed 29 September 2026
Symptoms
- Check engine light on
- Increased emissions
- Possible drop in fuel efficiency
Common causes
- Catalytic converter degradation
- Previous misfires
- Oxygen sensor issues
How to check it yourself
- Check for any misfire codes
- Inspect oxygen sensors for proper function
- Examine catalytic converter for damage
Can I keep driving?
The car can be driven, but emissions may be higher than normal.
General guidance, not a professional inspection. Confirm faults with measurements before buying parts, and use a qualified mechanic for brakes, steering, fuel leaks, airbags, and other safety-critical work. Terms and disclaimer