1997 Lincoln Mark VIII Owner's Manual - Page 250

3. To replace the fuel cap, align the tabs on the cap with the notches on the filler pipe. Push down and turn it clockwise until it stops. Push the fuel door closed. WARNING If you do not use the proper fuel cap, the pressure in the fuel tank can damage the fuel system or cause it to work improperly in a collision. Choosing the Right Fuel Use only UNLEADED FUEL. The use of leaded fuel is prohibited by law and could damage your vehicle. Your vehicle was not designed to use fuel containing manganese-based additives such as MMT. Additionally, vehicles certified to California emission standards (indicated on the underhood Vehicle Emissions Control Information label) are designed to operate on California reformulated gasolines. If California reformulated gasoline is not available when you refuel, your vehicle can be operated on non-California fuels. However, even though your engine will perform adequately on other gasolines, the performance of the emission control devices and systems may be adversely affected. Repair of damage caused by using a fuel that your vehicle was not designed for may not be covered by your warranty. 4. NOTE: If you replace your fuel cap with an aftermarket fuel filler cap, the customer warranty may be void for any damage to the fuel tank and/or fuel system. 245