P0430 — Catalyst System Efficiency Below Threshold (Bank 2)
Category: Powertrain Severity: Medium
Updated:
DTC code P0430 means: Catalyst System Efficiency Below Threshold (Bank 2). It falls under the "Powertrain" category, with an estimated severity of Medium. Common causes include failed catalytic converter, faulty oxygen (O2) sensor and exhaust leak; it's worth confirming the diagnosis before replacing parts.
Possible causes
- Failed catalytic converter
- Faulty oxygen (O2) sensor
- Exhaust leak
- Engine misfire
Symptoms
- Check engine light
- Rotten egg smell
- Loss of power
- Higher fuel consumption
How to diagnose it step by step
- Rule out misfires and other codes.
- Look for bank 2 exhaust leaks.
- Compare bank 2 upstream and downstream sensors.
- Replace the downstream sensor or the converter as indicated.
How to fix it
Rule out leaks and O2 sensors before replacing the catalytic converter (the most expensive part).
Estimated repair cost
O2 sensor: $100–280. Converter: $400–2,500.
Frequently asked questions
What does DTC code P0430 mean?
Catalyst System Efficiency Below Threshold (Bank 2).
Is code P0430 serious?
Severity Medium. Not urgent, but worth diagnosing to avoid bigger damage.
Can I keep driving with code P0430?
Yes, as with P0420: not urgent, but fix it before an emissions test.
Related codes
P0431 P0421 P0420 P0440 P0441 P0442 P0443 P0446 P0447 P0449
Refine by car make
- Audi P0430: Bank 2 catalytic converter or exhaust leak.
- BMW P0430: Catalytic converter or O2 sensor (bank 2).
- Citroën P0430: Catalytic converter or O2 sensor.
- Ford P0430: Bank 2 catalytic converter or O2 sensor.
- Honda P0430: Bank 2 catalytic converter or O2 sensor.
- Mercedes-Benz P0430: Bank 2 catalytic converter or O2 sensor.
- Opel P0430: Bank 2 catalytic converter or O2 sensor.
- Peugeot P0430: Bank 2 catalytic converter or O2 sensor.
- Renault P0430: Bank 2 catalytic converter or O2 sensor.
- Toyota P0430: Bank 2 catalytic converter.
- Volkswagen P0430: Bank 2 catalytic converter or exhaust leak.
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