Use regular unleaded gasoline rated at 87 octane or higher. GM recommends that the gasoline meet the specifications which have been developed by the American Automobile Manufacturers Association (AAMA) and endorsed by the Canadian Motor Vehicle Manufacturers Association for better vehicle performance and engine protection. Gasoline meeting the AAMA specification could provide improved driveability and emission control system performance compared to other gasoline. For more information, write to: American Automobile Manufacturer's Association, 7430 Second Ave., Suite 300, Detroit, MI, 48202.

Be sure the posted octane is at least 87. If the octane is less than 87, you may get a heavy knocking noise when you drive. If the engine knock is bad enough, your engine may be damaged.

If you are using fuel rated at 87 octane or higher and you hear heavy knocking, your engine needs service. Do not worry if you hear a little pinging noise when you are accelerating or driving up a hill. This is normal and you do not have to buy a higher octane fuel to get rid of pinging. Only the heavy, constant knock means that you have a problem.

Notice: Your vehicle was not designed for fuel that contains methanol. Do not use methanol fuel which can corrode metal parts in your fuel system and also damage plastic and rubber parts. This kind of damage would not be covered under your warranty.

If your vehicle is certified to meet to meet California emission standards, indicated on the under hood emission control label, is designed to operate on fuels that meet California specifications. If such fuels are not available in states adopting California emission standards, your vehicle operates satisfactorily on fuels meeting federal specifications, but emission control system performance may be affected. The malfunction indicator lamp on your instrument panel may turn on, and/or your vehicle may fail a smog-check test. If this occurs, return to your authorized dealer for diagnosis to determine the cause of failure. In the event that the cause of the condition is determined to be the type of fuels used, repairs may not be covered by your warranty.

Some gasoline that are not reformulated for low emissions may contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT). Ask your service station operator whether or not the fuel contains MMT.