I know this isn't about a F150 but maybe ya'll can help.
I just tried filling my 93 Ranger STX and it got to about .25 gallons and stopped. Tried a different pump too.So, a (much more mechanically savvy) friend and I started troubleshooting the problem.First we went to the station and tested to see if the filler air tube(?) was pinched or if the charcoal canister was clogged. Didnt appear to be clogged. He even blew air back to the tank to see. (using a straw to blow thru no the tube). So then we ran a plastic weed trim line thru to see if it got stuck. It did at about 2 feet but that is also the same distance that the fill pipe meets the tank at a sharp angle.Other than some SOB sticking a rag in my tank is there anything else that I should think is wrong?Any suggestions on how to fix?Thanks.

 

Not sure, Heres a guess. Does this thing have a roll over valve? Its a valve that closes so that if you roll over you don't spill fuel.
FWIW,
Jes

 

I have had the same issue with several vehicles before. I would place the nozzle as far into the tank as possible, and the pump would begin clicking after only a small amount of gas was in the tank. Turns out all I had to do was back the nozzle out of the tank about an inch or two and the rest of the tank would fill without any problem. Your problem might not be as simple as this but it is worth a try. Good luck.