P0418 Code ! 2001 Trans Am Ws6 M6

[FirehawkM6]

I've been having this code for weeks now. I replaced the air pump relay and the air check valves and just replaced the air pump yesterday with a new one and the code is still present ! And the SES light. My car is running rich at idle almost at 1600 rpms and my engine is running rich as well... Don't know what else to do ! I drive the car 5 days a week approximately 20 miles a day , would any harm be done to my car driving it in the condition it's in??

Any help or advice is appreciated

[FirehawkM6]

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