P0430 on a Hyundai: Causes, Fixes & Repair Cost

🟠 Moderate severity · drivable

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

What P0430 means on a Hyundai

On a Hyundai, P0430 means the downstream oxygen sensor on bank 2 reports that the catalytic converter isn't cleaning exhaust efficiently. It's the bank 2 version of P0420 and shows up mainly on V6 Hyundais.

Is P0430 common on Hyundais?

V6 Hyundai models like the Palisade, Santa Fe, and older Sonatas are where this code normally appears, usually at higher mileage. A failing converter or a worn downstream oxygen sensor are the two most common culprits.

Commonly reported on: Palisade, Santa Fe, Sonata.

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	$600–2400