P0430 on a Honda: Causes, Fixes & Repair Cost

🟠 Moderate severity · drivable

Drivable in the short term, but the bank 2 converter problem should be diagnosed soon.

What P0430 means on a Honda

On a Honda, P0430 means the downstream oxygen sensor on bank 2 says the catalytic converter isn't cleaning exhaust as well as it should. It's the bank 2 twin of P0420 and mostly shows up on Honda V6 models.

Is P0430 common on Hondas?

Honda V6 models like the Accord, Pilot, and Odyssey see P0430 at higher mileage, when converters and oxygen sensors start to wear. A misfire or rich fuel mixture that goes unfixed can also damage the converter over time.

Commonly reported on: Accord, Pilot, Odyssey, Ridgeline.

Symptoms

Check engine light is on
Reduced fuel economy
Possible rotten-egg smell from the exhaust
Often no noticeable driving symptoms early on

Common causes

most common: Worn or failing catalytic converter on bank 2
common: Faulty downstream oxygen sensor on bank 2
common: Exhaust leak before or near the downstream sensor
less common: Unfixed misfire or rich fuel mixture that damaged the converter

How to fix it

Fix	DIY?	Typical cost
Inspect for exhaust leaks and repair them before replacing anything	Yes	$50–200
Test the downstream oxygen sensor and replace it if faulty	Yes	$60–200
Replace the bank 2 catalytic converter	Mechanic	$700–2500