Oldsmobile 2004 Silhouette Owner's Manual page 310

While refueling, let the fuel cap hang by the tether
as shown.
5-8
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CAUTION:
If you spill fuel and then something 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.
Don't top off or overfill your tank, and wait a few
seconds after you've finished pumping before you
remove the nozzle. Be careful not to spill fuel. Clean
fuel from painted surfaces as soon as possible.
See Cleaning the Outside of Your Vehicle on page 5-95 .
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 3-49 .