What does code P0430 mean on a Buick and is it safe to drive?
P0430: Catalyst System Efficiency Below Threshold (Bank 2). Here's what it means on your Buick, 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 Buick
- 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 Buick, 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 Buick
Buick 3.6L V6 P0430 bank 2 catalyst follows the same diagnosis as P0420. Evaluate fuel trims on both banks before condemning the converter—the LFX and LGX engines can develop oil consumption issues that poison bank 2 catalysts ahead of bank 1.
Most commonly affected models
Enclave 3.6L 2008–2017LaCrosse 3.6L 2010–2016