I just took my car to the refferee and passed both the visual and emissions test, i failed the functional due to my check light comming on because of my knock sensor at the end of the test. My question is "does octane effect emmissions?" I was just thinking of throwing a bottle of octane booster in my tank so i could take the test and wouldnt have to worry about the engine pinging. timing is already low at 15 TDC.