1997 Lincoln Mark VIII Owner's Manual - Page 249

If the fuel door does not open when you push the release button, open the trunk and find the override release on the right side. The override release is a handle which says FUEL FILLER DOOR RELEASE MANUAL OVERRIDE. Open the fuel door by pulling on the handle. 1. Turn the engine off. After opening the fuel door, remove the cap carefully and slowly by pushing it down and turning it counterclockwise 1/8 turn until it stops. Pull to remove the cap. A tether attaches the cap to the fuel filler pipe. WARNING The fuel system may be under pressure. If the fuel cap is venting vapor or if you hear a hissing sound, wait until it stops before completely removing the cap. 2. Make sure that you pump premium unleaded fuel and put the nozzle all the way inside the fuel filler pipe. The fuel filler door manual release - located inside the trunk NOTE: If you spill any fuel on the body of your vehicle, clean it off immediately. The fuel may dull or soften the paint if you do not wash it off. 244