Hi. I put my F-150 back on the road after 6 months. 4X4 4.9L Duel tanks. I flushed out the tanks, did a full tune up and put a new fuel filter in but couldn’t get her to start. Fuel pumps tested fine and had no bad fuse so I went by the ford dealership and talked with one of the mechanics. He said to check the ground on a module on the fender. ( FCM ? ) I can’t remember the name. Anyway, I found it removed it and sanded the back and reinstalled and she fired right up! But I still had a problem. I had to let it run for about 15 mins before driving or she would stall. Other than that it drove great. Till today! I stalled after about 5 miles at a stop light. After about ten turns of the key it fired up like nothing happened only to stall again a mile down the road. Never to start again. Anyone have any idea what the problem could be. Any help would be greatly appreciated!

 

Put a fuel pressure gauge on the fuel rail, I bet you got a bad pump. Another check when it dies is to depress the schrader valve on the fuel rail, if it squirts fuel it is not the pump. If fuel trickles out or doesn't come out at all it's not getting fuel.
Warning: fuel and a hot motor causes fires. Carefully....