1995 Pontiac Firebird Owner's Manual - Page 237

Fuel ~ 5 7 LT1 (Code P) .L The 8th digit of your vehicle identification number (VIN) shows thecode letter for your engine.You will left find the VIN at the top of your instrument panel. (See "Vehicle Identification Number" the Index.) in Use premium unleaded gasoline rated at 91 octane or higher for bestperformance. You m y use middle grade or regular unleaded gasolines, but your vehicle may not accelerate as well. The gasoline you use should meet speakations ASTM D4814 in the United States and CGSB 3.5-92 in Canada. These fuels should have the proper additives,so you should not have to add n w g to the fuel. a In the United Statesand Canada, it's easyto be sure you get the right kindof gasoline (unleaded). You'll see UNLEADED righton the pump. And only unleaded nozzles will fit into your vehicle's filler neck. Be sure the posted octane for premium is at least (at 91 least 89 for middle grade and for regular).If the octane 87 is lessthan 87, you may get a heavy hocking noise when you drive. If it's bad enough,it can damage your engine. If you're using fuel rated at91 octane or higher and you still hear heavy knocking, your engine needs service. But don't worry you hear a little pinging noise when if you're acceleratingor driving up a hill. That's normal and you don'thave to buy a higher octane fuel to get rid of pinging. It'sthe heavy, constant knock that means you have a problem. What about gasoline with blending materials that contain oxygen (oxygenates), such MTBE or alcohol? as MTBE is "methyl tertiary-butyl ether." Fuel thatno is 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. NOTICE: Fuel that is more than5% methanol is bad for your vehicle. Don't use it. can corrode metal It parts in your fuel system and also damage plastic and rubber parts. That damage wouldn't be covered under your warranty. And even 5% or at less, there must be "cosolvents" and corrosion preventers in this fuel to help avoid these problems. ' ~ I 6-4 _ r i