P0430: Catalytic converter efficiency below threshold (Bank 2)
Drive carefully. Get it checked within a week or two.
Can I drive with P0430?
Yes, but drive carefully and get it checked soon. Bank 2 catalytic converter is failing to clean exhaust emissions; vehicle remains drivable.
What does P0430 mean?
P0430 stands for Catalyst System Efficiency Below Threshold (Bank 2).
Symptoms you may notice
- Check engine light stays steadily illuminated
- little noticeable loss in driving power or throttle response
- Rotten egg / sulfur odor from tailpipe in some cases
- Automatic failure during state emissions inspection
How much does it cost to fix?
Repair costs for code P0430 depend on the specific underlying root cause, ranging from simple DIY checks to component replacement. The table below lists the most common causes and rough price ranges in USD:
- Worn Bank 2 catalytic converter core
- Exhaust leak near Bank 2 manifold or downpipe
- Faulty Bank 2 Sensor 2 oxygen sensor
- Past misfires on Bank 2 cylinders that overheated the cat
What to do next
- Inspect the Bank 2 exhaust downpipe for cracks or loose hardware.
- Graph downstream Bank 2 oxygen sensor voltage; if it mirrors upstream, catalyst is degraded.
- Fix any Bank 2 misfires before installing a replacement catalytic converter.
Last updated: October 2026
Related codes
General guidance only, not a professional diagnosis. If the check-engine light is flashing, or the car is running rough, overheating or losing power, stop driving and get help.
About this code
Code P0430 is the Bank 2 equivalent of P0420 on dual-bank engines (V6, V8, and V10). It signals that the Bank 2 catalyst efficiency has fallen below the 95% threshold required by emissions regulations. Your vehicle will drive normally without any noticeable loss in power, but the yellow check engine light will stay on.