1997 Buick Park Avenue Owner's Manual - Page 268

If you have the3800 Supercharged engine (VIN Code l), use premium unleaded gasoline rated at 91 octane or higher. With the 3800 Supercharged engine, in an emergency, you maybe able to use a lower octane -- as low as 87 -- if heavy knocking does not occur. If you are using 91 or higher octane unleaded gasoline and you hear heavy knocking, your engine needs service. At a minimum, the gasoline you use should meet specifications ASTM D4814 inthe United States and CGSB 3.5-M93 in Canada. Improved gasoline specifications have beendeveloped by the American Automobile Manufacturers Association (AAMA) for better vehicle performance and engine protection. Gasolines meeting the AAMA specification could provide improved driveability and emission control system protection compared to other gasolines. Be surethe posted octane for premium is at least91 (at least 89 for middle grade and 87 for regular). If the octane is less than 87, you may get a heavy knocking noise when you drive. If it's bad enough, it can damage your engine. If your vehicle is certified to meet California Emission Standards (indicated on the underhood tune-up label), it is designed to operate on fuels that meet California specifications. If such fuels are not available in states adopting California emissions standards, your vehicle will operate satisfactorily on fuels meeting federal specifications, but emission control system performance may be affected. The malfunction indicator lamp on your instrument panel may turn and/or your vehicle on may fail a smog-check test. If this occurs, return to your authorized Buick dealer for diagnosis to determine the cause of failure. In the event it isdetermined that the cause of the condition is the type of fuels used, repairs may not be covered by your warranty. Some gasolines that are not reformulated for low emissions contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT); ask your service station operator whether or not his fuel contains MMT. General Motors does not recommend the use of such gasolines. If fuels containing MMT are used, spark plug life may be reduced and your emission control system performance may be affected. The malfunction indicator lamp on your instrument panel may turn on. If this occurs, return to your authorized Buick dealer for service. 6-4