What does code P0430 mean on a GMC and is it safe to drive?
P0430: Catalyst System Efficiency Below Threshold (Bank 2). Here's what it means on your GMC, what usually causes it, what repairs typically cost, and how safe it is to keep driving.
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What this code means
Same as P0420 but for bank 2. The catalytic converter on bank 2 is not operating efficiently.
Common causes for your GMC
- Failed catalytic converter (bank 2)
- Faulty O2 sensor(s)
- Exhaust leak
Symptoms
- Check Engine Light
- May fail emissions
Typical fixes
- Replace bank 2 catalytic converter
- Replace oxygen sensors
- Repair exhaust leaks
Repair cost range
For a GMC, repairs for P0430 often fall between $400 and $2400, depending on the cause and whether you use OEM or aftermarket parts. Labor rates vary by location.
Known issues on GMC
GMC P0430 on V8 trucks mirrors Chevrolet's bank 2 catalyst diagnosis. On LS V8 engines, evaluate both bank fuel trims before replacing the converter—a rich condition on bank 2 from an O2 sensor or injector fault will destroy a new converter quickly.
Most commonly affected models
Yukon/Yukon XL 5.3L 2007–2014Sierra 5.3L/6.0L 2007–2014Envoy 4.2L 2002–2009