The gas door on my 2016 Ford F-150 wouldn’t spring closed and would blow open in the wind.
Close the fuel door. Laying under the bed and looking upward, you can see the back of the fuel door. There is a plastic rod / hinge with a metal spring that locks on to a tab under the fuel door. The plastic rod is keyed to fit in to the fuel door arm / hinge. You can see in the photo that the keyed rod has dropped down out of the door, so it’s no longer engaged into the door, which is why it’s blowing open and not springing shut.
Using a flathead screwdriver, you can pop the end of the spring out of its locking tab.
With the spring disconnected, rotate the rod to the right so the keyed slot in the rod is lining up with the arm on the fuel door. Once it’s lined up, push the rod up and into the fuel door.
With the rod lined up and pushed back up in place, you can use the screwdriver to push the spring back in to its locking tab. Push the spring along the tab until the springs curve snaps into place on the tab.
Application:
2015-Newer Ford F-150
Conclusion:
This is a pretty easy repair. I hope this helps.