1998 Buick Century Owner's Manual - Page 266

The tethered cap is behind a hinged door on the left side of your vehicle. If you get gasolineon yourselfand then something ignites it, could be badly burned. you Gasoline can spray out you if you open the on fuel filler cap too quickly. This spray can happen if your tank is nearly full, and more likely in is slowly and hot weather. Open the fuel filler cap wait for any "hiss" noise to stop. Then unscrew the cap all the way. Be careful not to spill gasoline. Clean gasoline from painted surfaces as soon as possible. See "Cleaning the Outside of Your Vehicle" in the Index. While refueling, let the cap hang by the tether below the fuel fill opening. To remove the cap, turn it slowly to left the (counterclockwise). The caphas a spring in it; if you let go of the cap too soon, it will spring back to the right. 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 the Index. 6-6