what is code 0430

[jefferson351]

can anyone help me with this code 0430?

[Quik_LS]

P0430 - Catalyst System Low Efficiency Bank 2

[shorod]

This is a generic OBD-II code (ie: same for all OBD-II cars). The definition is: P0430 - Catalyst System Efficiency Below Threshold (Bank 2). According to the factory service manual, some common causes for this code are:

• Use of leaded fuel
• Damaged HO2S
• Malfunctioning ECT
• High fuel pressure
• Damaged exhaust manifold
• Damaged catalytic converter
• Oil contamination
• Cylinder misfiring
• Downstream HO2S wires improperly connected
• Damaged exhaust system pipe
• Damaged muffler/tailpipe assembly
• Retarded spark timing

The service manual suggests troubleshooting it by:
Compare HO2S upstream and downstream switch rate and amplitude. Under normal closed loop fuel conditions, high efficiency catalysts have oxygen storage which makes the switching frequency of the downstream HO2S very slow and reduces the amplitude of those switches as compared to the upstream HO2S. As catalyst efficiency deteriorates, its ability to store oxygen declines and the downstream HO2S signal begins to switch more rapidly with increase amplitude, approaching the switching rate and amplitude of the upstream HO2S. Once beyond an acceptable limit the DTC is set.

Based on the history of faulty coils due to leaking valve cover gaskets, I'd suggest you start by pulling the coils and checking for any that are oil contaminated. If you find one or more, you'll need to replace the valve cover gaskets to keep it from destroying a new coil as well. You most likely won't be able to just clean the oil off the coil, replace the valve cover gasket, and reuse the coil.

For future posts, please reference the year and engine of your car. That will help us go in to more specifics.

-Rod

[Towncar]

Interesting... I'm sure I posted in this thread around 06:50 last night...
Is there some Mod. playing God here? Hey, I'm a poet too

[shorod]

Wasn't me, and I'm not seeing any missing posts....

-Rod

[jefferson351]

Thanks