1999 Cadillac DeVille Owner's Manual - Page 276

yellowblue The fuel door release button is located to the left of the steering wheel next to the headlamp knob and on the remote keyless entry transmitter. The button only works in PARK (P) or NEUTRAL (N) when the ignition key is in any position and the VALET lockout button is in the OFF position. An alternate fuel door release is located inside of the trunk on the driver's side. Pull it to release the fuel door. While refueling, hang the cap by the tether from the hook on the filler 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