Chevrolet 2003 Silverado 1500 Pickup Owner's Manual page 383

While refueling, hang the fuel cap by the tether using
the hook located on the inside of the filler door.
To remove the fuel cap, turn it slowly to the left
(counterclockwise).
If you get fu on yourself and t..,' n so met^ lg
ignites it, you could be badly burned. Fuel can
spray out on you if you open the fuel cap too
quickly. 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 gasoline. Clean gasoline from
painted surfaces as soon as possible. See Cleaning the
Outside of Your Vehicle on page 5- 105.
When you put the fuel 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 on
page 3-44.
Notice: If you need a new fuel cap, be sure to get the
right type. Your dealer can get one for you. If you get
the wrong type, it may not fit properly. This may
cause your malfunction indicator lamp to light and
may damage your fuel tank and emissions system.
See "Malfunction Indicator Lamp" in the Index.
5-8