Some gas tanks have a locking system. This is to prevent gas theft from your automobile. It is also a method of keeping the gas cap from popping open while you are driving. Though typically easy to lock and unlock without a problem, these locking gas tanks occasionally get stuck. There are a few methods of getting that gas tank open without damaging any part of the car. It just takes a little finesse and experimentation.
Open the trunk of your car.
Remove the carpet that covers the interior wall of your trunk on the side of the gas tank. It will easily pull from the surface of the car.
Press the manual release button. It will be located near the gas tank.
Pull the gas-tank lever upward. It is located on the interior driver's side of the car.
Find the gas tank release cable. It is located under the lever.
Pull the gas tank release cable. Use needle-nose pliers to do this. This will forcefully release the gas tank.