yeah, i've never really had any sort of luck with anything like that. Eithe good or bad. I did burn up an O2 sensor in my 90 lumina using octan boost "safe for all O2 sensors", (my ass). In My opinion, your money is better saved on that crap, and spent on gm top engine cleaner. Disable the fuel pump by pulling the relay, sturt it and let it run till it dies, hook this stuff up to the shrader valve on the fuel rail, and start it up and let it run on this stuff. Smokes like hell, but it'll get the job done.