P0430: bank 2's catalytic converter isn't cleaning up well enough
The catalytic converter is the part of the exhaust that cleans up the gases before they leave the car, and the engine control unit checks how well it's doing that by comparing the oxygen sensors before and after it. This code means that comparison shows bank 2's converter isn't cleaning the exhaust as effectively as the computer expects. It's a statement about the exhaust's performance, not automatically a statement about which part has failed.
You might notice
- No symptom you'd feel while driving, beyond the engine warning light coming on
- catalytic converter
- — the part of the exhaust that cleans up the gases before they leave the car
- oxygen sensor
- — a sensor in the exhaust that measures how much oxygen is left after combustion
- bank 2
- — the second side of an engine built with two cylinder banks, such as a V6 or V8
What the code itself says
P0430 is a powertrain (engine, gearbox and drive system) code, and the 0 after the letter means it is a generic code with a standard meaning.
Grouped here as: Engine running, fuelling and misfires — Air metering, fuelling, ignition, misfire, idle, boost, knock, oxygen sensors and the catalyst, all working together in the running engine. That grouping is ours, to help explain the code. The code's official family is the letter at the start.
This page is generic. Your car isn't.
A code on its own only tells you what the sensor saw, not what's actually wrong — and that changes next to your other codes. Read this one together with the rest of your scan and we'll work out what's really going on.
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