Zengineer

A few months ago, I received a P0430 code. Cat efficiency below threshold bank 2.

I reset the code and drove for a few months with no problems. The code comes back and I reset it again. I drive for about a month and the code returns.

*Mind you, the permanent code does go away after the proper drive cycle.

Now, the code appears about once a week. I changed all 4 O2 sensors over the weekend, reset the codes, and the permanent code disappeared. About 30 miles later, the code reappears.

Is this characteristic of the driver side cat going bad? or bad fuel injectors? The spark plugs were changed about 50k miles ago (60k miles, I'm at 108k now.)...perhaps a plug change next? thoughts?

*I also tossed in some cat cleaner in the gas tank over the weekend. I might run the tank until empty and see if the code returns.

thanks!