Hello, Scotty. I have a 2002 Chevrolet Prizm that keeps throwing a P0303 code.I have changed spark plugs, coil on boots, valve cover gasket and cykinder seals. The #3 cylinder did have oil in it but that is now gone. The new plug in cylinder 3 is firing, it looks to be carbon residue.
I can clear the code, start and drive the car without the code reappearing. However, when I turn the car off and restart it, the code reappears. Any thoughts on why it would do that?