going from 91 to 87 gave me CEL! FLAME ON

[mikenacarato]

Originally Posted by The little red pill

that's what you get for using 87 octane. Not only do I use 93, but I add octane booster to give me about 97 octane. I even have a NOS sticker on my car to prove how cool I am!

Seriously though, most likely the gas cap! I had it happen to me on a different car. I actually had to get a new gas cap, because the rubber gasket on mine was bad.

you know you will foul your plugs out right? octane increased additives will burn them up. if you have been doing it for a few tanks, pull a plug and see if its turning an orangy burnt color. your eating away the electrodes.