Cranks but no start, mostly if engine hot

Sometimes truck will crank but not start when cold but usually it is when I drive around for while. Engine gets hot and I turn off to run in a store and when I come out it will start but then proceed to run rough then out of gas. Then it will just keep cranking and no start. Took to get diagnosed and could not find any codes or problems. The weird thing is once started it runs great just afraid to stop it anywhere. I thought maybe fuel pump but I have no issues when truck is started. I think it might be ignition switch or crankshaft censor. I have spark cause if I squirt a little gas into the throttle body it will start up. It is like something is telling the fuel pump not to turn on. So once engine is normal operating temperature and I stop somewhere when I try to start it back up sometimes it will start up and other times it will start for a second run rough and then out of gas. I cannot afford to take into dealer and have them throw parts into it when they cannot fine the problem. Once the engine cools down it will almost always fire up no problem.