1995 Pontiac Grand Prix Owner's Manual - Page 216

Fuel Use regular unleaded gasoline rated at 87 octane or higher. It should meet specifications ASTM D4814 i.n the United States and CGSB 3 5 9 2 in Canada. These hels should have the proper additives, so you should not have to add anything to the fuel. What about gasoline with blendingmaterials that contain oxygen (oxygenates), such as MTBE or alcohol? MTBE is "methyl tertiary-butyl ether." Fuel that is no more than 15%MTBE is fine for your vehicle. Ethanol is ethyl or grain alcohol. Properly-blended fuel your that is no more than 10%ethanol is fine for vehicle. Methanol is methyl or wood alcohol. h the United States and Canada, it's easy tobe sure you get the right kind of gasoline (unlea.ded).You.'ll see UNLEADED right on the pump. And only unleaded nozzles will fit into your vehicle's filler neck. 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 it's bad enough, it can damage yourengine. Lf you're using fuel rated at 87 octane or higher and you still hear heavyhocking, your engine needs service. But don't worry if you hear a little pinging noise when you're accelerating or driving up a hill. That's normal, and you dan't have to buy a higher octane fuel to get rid of pinmg. It's the heavy, constant knock that means you have a problem. Fuel that is more than 5% methanol is bad for your vehicle. Don't use it. It can corrode metal parts in your fuel system and also damage plastic be and rubber parts, That damage wouldn't covered under your warranty. And even5at or % less, there must be "cosolvents'' and corrosion preventers in this fuel to help avoid these 6-3