1993 Pontiac Bonneville Owner's Manual - Page 224

[n the U.S. and Canada, it's easy to be sure you get the right kind of gasoline 'unleaded). You'll see "UNLEADED" Pight on the pump. And only unleaded specifications ASTM D4814 in the U.S. aozzles will fit into your vehicle's filler and CGSB 3.5-92 in Canada. These neck. fuels should have the proper additives, so you should not have to add anything B sure the posted octane is at least e 87. [f the octane is less than you may get to the fuel. 87, 1 heavy knocking noise when you drive. In the U.S. and Canada, it's easy to be [fit's bad enough, it can damage your sure you get the right kind of gasoline :ngine. (unleaded). You'll see "UNLEADED" [f you're using fuel rated at octane or right on the pump. And only unleaded 87 nozzles will fit into your vehicle's filler nigher and you still hear heavy neck. knocking, your engine needs service. But don't worry if you hear a little Be sure the posted octaneis at least 91. inging noise when you're accelerating If the octane is less than 91, you may get 3r driving up a hill. That's normal, and a heavy knocking noise when you drive. vou don't have to buy a higher octane (In an emergency,you may be able to Fuel to get rid of pinging. It's the heavy, use lower octane-as low as 87-if :onstant knock that means you have a heavy knocking does not occur.) If xoblem. you're using 91 or higher octane unleaded gas andyou still get heavy knocking, your engine needs service. 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 that is no more than 10%ethanol is fine for your vehicle. Methanol is methyl or wood alcohol.