2001 GMC Sonoma Owner's Manual - Page 270

To provide cleaner air, all gasolines in the United States are now required to contain additives that will help prevent deposits from forming in your engine and fuel system, allowing your emission control system to function properly. Therefore, you should not have to add anything to the fuel. In addition, gasolines containing oxygenates, such as ethers and ethanol, and reformulated gasolines may be available in your area to contribute to clean air. General Motors recommends that you use these gasolines, particularly if they comply with the specifications described earlier. Fuel E-85 (85% Ethanol) The 8th digit of your vehicle identification number (VIN) shows the code letter for your engine. You will find the VIN at the top left of your instrument panel. See "Vehicle Identification Number" in the Index. If you have the 2200 L4 (Code 5) engine, you may use either regular unleaded gasoline or ethanol fuel up to 85% (E-85); also see "Fuel (Gasoline)" listed previously. If you have the 4.3L V6 engine use only regular gasoline. Only vehicles with the 2200 L4 (Code 5) engine may use 85% ethanol fuel (E-85). Most service stations will not have an 85% ethanol fuel (E-85) pump available. Those stations that do have E-85 should have a label indicating minimum ethanol content. Do not use the fuel if the minimum ethanol content is greater than 85%. Your vehicle may not operate properly if the ethanol content is greater than 85%. At a minimum, E-85 should meet ASTM D 5798 specifications. NOTICE: Your vehicle was not designed for fuel that contains methanol. Don't use it. It can corrode metal parts in your fuel system and also damage plastic and rubber parts. That damage wouldn't be covered under your warranty. 6-5