Ford F-150 1988

While driving down the road my 88 F-150 (5.0)EFI, started sputtering like is was running out of gas and subsequently quit running. I had switched tanks from the forward to rear tank about a 1-2 miles earlier so I quickly switched back but it did not help. I checked the fuel line by removing the cap and depressing the valve stem and no fuel came out. I cycled the ignition on and off to prime the fuel line and eventually filled the line back up but when you try to start the car it initially acts like it wants to start then you lose spark and fuel, its as though a safety switch of some sorts is telling it to stop fuel flow and ignition. When you cycle the key to the run position you can hear the fuel pump energizing, oil level, pressure good. Any suggestions.