2008 Cadillac STS Owner's Manual - Page 326

The tethered fuel cap is located behind a hinged fuel door on the passenger's side of the vehicle. {CAUTION: Fuel can spray out on you if you open the fuel cap too quickly. If you spill fuel and then something ignites it, you could be badly burned. This spray can happen if your tank is nearly full, and is more likely in hot weather. Open the fuel cap slowly and wait for any hiss noise to stop. Then unscrew the cap all the way. Be careful not to spill fuel. Do not top off or overfill the tank, and wait a few seconds after you have finished pumping before removing the nozzle. Clean fuel from painted surfaces as soon as possible. See Washing Your Vehicle on page 5-110. When replacing the fuel cap, turn it clockwise until it clicks. Make sure the cap is fully installed. 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 on page 3-68. To open the fuel door, apply pressure in the center of the rear edge of the fuel door and it will pop open. To remove the fuel cap, turn it slowly counterclockwise. The fuel cap has a spring in it; if the cap is released too soon, it will spring back to the right. While refueling, hang the tethered fuel cap from the hook on the fuel door. 5-8