1997 Chevrolet Lumina Owner's Manual - Page 235

Adding Equipment to the Outside of Your Vehicle Things you might add to the outside your vehicle can of affect the aifflow around it. This may cause wind noise and affect windshield washer performance. Check with your Chevrolet dealer beforeadding equipment to the outside of your vehicle. If you're using fuel rated at 87octane or higher and you hear heavy knocking, your engine needs service.But don't worry if you hear little pinging noise when a you're accelerating or driving up a hill. That's normal, and you don'thave to buy ahigher octane fuel to get rid of pinging. It's the heavy, constant knock that means you have a problem. If your vehicle is certified to meet California Emission Standards (indicated on the underhood tune-up label), it is designed to operate on that meet California fuels specifications. If such fuels are not available states in adopting California emissions standards, your vehicle will operate satisfactorily on fuels meeting federal specifications, butemission control system performance may be affected.The malfunction indicator lamp on your instrument panel may turn on and/or your vehicle may fail a smog-check test.If this occurs, return to your authorized Chevrolet dealer for diagnosis todetermine the cause of failure. Inthe event it isdetermined that the cause of the conditionis the typeof fuels used, repairs may not becovered by your warranty. Use regular unleaded gasoline rated 87 octane or at higher. At a minimum, should meet specifications it ASTM D4814 in the United States and CGSB 3.5-M93 in Canada. Improved gasoline specificationshave been developed by the AmericanAutomobile Manufacturers Association (AAMA) for better vehicleperformance and engine protection. Gasolines meeting the AAMA specification could provide improved driveability and emission control system protection compared to other gasolines. Be sure the posted octane is at least 87. the octane is If less than 87, you may get a heavy knocking noise when you drive. If it's bad enough, it can damage your engine.