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Q: What is the best fix for a catalyst system efficiency below threshold (bank 2)

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i got a fault code reading of p0430 on my 2003 ford expedition

My car has 225000 miles.
My car has an automatic transmission.

Trouble code P0430 is for a catalyst on the drivers side. The sensor after the converter may be bad and not responsive enough or the catalyst itself may be bad.

The catalyst should be replaced if the converter rattles, there is a loss of power, or the spark plugs run richer on the drivers side more than the right passenger side of the engine.

If you’d like to have this fixed, consider YourMechanic, as one of our mobile technicians can come you, perform these checks, and diagnose the trouble code further in order to make an accurate repair.

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