1996 Pontiac Firebird Owner's Manual - Page 243

You can be injured and your vehicle could be damaged ifyou try to do service work on a vehicle without knowing enough about it. 0 Be sure you have sufficient knowledge, experience, and the proper replacement parts and tools before you attempt any vehicle maintenance task. Be m e to use the proper nuts, bolts and other fasteners. "English" and "metric" fasteners can be easily confused. If you use the wrong fasteners, parts can later break or fall off. You could be hurt. L If you have the5.7LCode P engine, use premium unleaded gasoline rated 9 1 octane or higher best at for performance.'You may use middle grade regular or unleaded gasolines, but your vehicle may not accelerate as well. At a minimum, the gasoline you use should meet spe'cificationsASTM D4814 in the United States and CGSB 3.5-M93 in Canada. Improved gasoline by specifications have been develope'd the American for Automobile Manufacturers Association (AAMA) better vehicle performance and engine protection. Gasolines meeting theAAMA specification could provide improved driveability and emission control system protection compared to other gasolines. Be sure the posted octane premium is at least 91 for (at least 89 for middle grade and for regular). If the 87 octane is less than you may get a heavy knocking 87, noise whenyou drive. If it's bad enough, it can damage your engine. If you're using fuel rated at the recommended octaneor higher and you hear heavy knocking,your engine still if needs service. But don't worry you hear a.little pinging noise when you're accelerating or driving a up h l . That's normal, and you don't haveto buy a higher il octane fuel to get rid pinging. It's the heavy, constant of knock that means you have problem. a Fuel The 8th digitof your vehicle identification number (VIN) shows the code letter your engine.You will for find theVIN at the top left of your instrument panel. (See "Vehicle Identification Number" in Index.) the If YQU don't havethe 5.7L Code P engine, use regular unleaded gasoline rated at87 octane or higher.