Cadillac 2001 Catera Owner's Manual page 257

You can also press the fuel button on the remote keyless
entry transmitter to access the fuel cap.
6-6
To open your fuel door,
your vehicle must be in
PARK (P). Press the
FUEL DOOR unlock
button located on the
instrument panel center
console to unlock and
open the fuel door.
Your vehicle has a tethered fuel cap.
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.