I took the car to autozone again to see why the check engine light's still on.
They didn't give a specific code, but said "bank one is running rich".
I asked about the chances of a new O2 sensor going bad & he pretty much said "slim to none".
Where can one find an AC/Delco O2 sensor reasonably priced?
I don't think it's an injector issue since it runs good. It's just getting less (3-4 mpg less) gas mileage than before.
Thanks.