Chevrolet 1999 Malibu Owner's Manual page 226

The cap is behind a hinged door on the right side of your
vehicle. To open the door, insert your finger into the
finger depression next to the fuel door.
While refueling, hang the tethered cap inside the
fuel door.
To remove the cap, turn it slowly to the left
(counterclockwise). The cap has a spring in it; if you let
go of the cap too soon, it will spring back to the right.
6-6
CAUTION:
If you get gasoline on yourself and then
something ignites it, you could be badly burned.
Gasoline can spray out on you if you open the
fuel filler cap too quickly. This spray can happen
if your tank is nearly full, and is more likely in
hot weather. Open the fuel filler cap slowly and
wait for any "hiss" noise to stop. Then unscrew
the cap all the way.
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