I drive a Subaru Forester 2001. I just made an oil change and converted from synthetic oil back to conventional since I don't feel seeing any benefits from synthetic oil. A couple weeks after that, CEL comes on and the code read as P0420 related to catalytic converter. I'm wondering whether it could be related to the oil change swinging between synthetic and conventional oil? Or it could just be just coincidence......
- posted
14 years ago