1998 Chevrolet Express Van Owner's Manual - Page 246
1998 Chevrolet Express Van Manual
Page 246 highlights
When you put the cap back on, turn it to the right (clockwise) until you hear a clicking sound. Make sure you fully install the cap. The diagnostic system can determine if the fuel cap has been left off or improperly installed. This would allow fuel to evaporate into the atmosphere. See "Malfunction Indicator Lamp" in theIndex. Filling a Portable Fuel Container /i\ CAUTIOlr: Never filla portable fuel container while it is in your vehicle. Static electricity discharge from the container can ignite the gasoline vapor. You can be badly burned and your vehicle damaged if this you occurs. To help avoid injury to and others: Dispense gasoline only into approved containers. Do not fill a container while it is insidea vehicle, in a vehicle's trunk, pickup bed or on any surface other than the ground. Bring the fill nozzle in contact with the inside of the fill opening before operating the nozzle. Contact should be maintained until the filling is complete. Don't smoke while pumping gasoline. NOTICE: If you need a new cap, be sure to get the right type. Your dealer can get one you. If you get for the wrong type, it may not fit properly. This may cause your malfunction indicator lamp to light and your fuel tank and emissions system may be damaged. See "Malfunction Indicator Lamp" in the Index.