1993 Pontiac Grand Am Owner's Manual - Page 200
1993 Pontiac Grand Am Manual
Page 200 highlights
Fuel 2.3L Quad OHC and Quad4 Engines (Codes 3 and D) and 3300 V6 Engine (Code N ) : The 8th digitof your Vehicle Identification Number (VIN) shows the code letter for your engine. will You find the VINat the top leftof your instrument panel. (See the d e x under I &hicle Identijkation Number.) Use regular unleaded gasoline rated at 87 octane or higher. It should meet specifications ASTM D4814 i the U.S. n and CGSB 3.5-92 in Canada. These fuels should have the proper additives, so you should not have to add anything to the fuel. In the U.S. and Canada, it's easy to be sure you get the right kind of gasoline (unleaded). 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 isat least 87. If the octane is less than 87, you may get a heavy knocking noise when youdrive. If it's bad enough, it candamage your engine. 1 s 9