1993 Chevrolet Cavalier Owner's Manual - Page 199

Fuel If you try to do your own servic work without knowing enough abot it, your vehicle could bedamaged. Use regular unleaded gasoline ratedat 87 octane or higher. It should meet specifications ASTM D4814 in the U.S. 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'sfiller neck. Be sure the posted octane is at least 87. If the octane is less than87, you may get a heavy knocking noise when you drive. If it's bad enough, it can damage your engine. If you're using fuel rated at87 octane or higher and you still hear heavy knocking, 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 don't have to buy a higher octane fuel to get rid of pinging. It's the heavy, constant knockthat means you have a problem. Fuel Capacity: 15.2 U.S. Gallons (57.5 L). Use unleaded fuel only. I97