I have replaced the gas cap five times and even had the oxygen sensor replaced. Yet the check engine light still comes on for a smog leak. I now have a Chevy dealership gas cap, I tighten it over three times, and it still has the check engine light on. I am not going to spend any more money on this car because of a simple gas cap. I have already checked and had the oil changed even though it didn't need it, had the fuel filter even replaced even though it didn't need it, and even went so far as replacing the spark plugs. I've done everything but a voodoo priestess dance for this car, so I need to know what will actually remedy this check engine light regarding the smog leak and gas cap issue. I am tired of being ripped off by the dealership. Thank you!