1998 Buick Skylark Owner's Manual - Page 227

To provide cleaner air, all gasolines in the United States Standards (indicated on the underhood emission control are now required to contain additives that will help label), itis designed to operate on fuels that meet prevent deposits from forming in your engine and fuel California specifications.If such fuels are not available system, allowing your emission control system to in states adopting California emissions standards, your function properly. Therefore, you should not have to add vehicle will operate satisfactorily on fuels meeting anything tothe fuel. In addition, gasolines containing federal specifications, but emission control system oxygenates, such as ethers and ethanol, and performance may be affected. The malfunction indicator reformulated gasolines may be available your area to in lamp on your instrument panel may turn on and/or your help clean the air. General Motors recommends that you vehicle mayfail a smog-check test. this occurs, return use these gasolines if they comply with the If to your authorized Buick dealer diagnosis to for specifications described earlier. determine the cause failure. In the eventit is of determined that the cause the condition is the type of of NOTICE: fuels used, repairs may not be covered your warranty. by Some gasolines that are not reformulated for low Your vehicle was not designed fuel that for emissions contain an octane-enhancing additive called contains methanol. Don't use it. It can corrode methylcyclopentadienyl manganese tricarbonyl (MMT); metal parts in your fuel system and also damage ask your service station operator whether not his fuel or contains MMT. General Motors does not recommend the plastic and rubber parts. That damage wouldn't use of such gasolines.If fuels containing MMT are used, be covered under your warranty. spark pluglife may be reduced and your emission control system performance may be affected. The on malfunction indicator lamp your instrument panel may turn on. If this occurs, return your authorized to Buick dealerfor service. I 6-4