I HAVE A 94 E150I ACTS LIKE IT IS RUNNONG OUT OF FUEL WHILE DRIVING BUT WHEN THE PEDAL IS PRESSED DOWN TO THE FLOOR IT RUNS FINE FOR A SHORT TIME THE IT DOES IT AGAIN

 

You could have weak fire or the timing could be off. When pressing the gas the timing could be advancing just enough to run alright temporarilly. I had a s-10 1991 model that acted the same way. I pulled the distributor cap off and the roor cap was missing the metal piece that ditributed the fire. When I put it on the floor though it would start to run though. IT WAS FIRING THROUGH THE PLASTIC ROTOR CAP.

 

thanks for the advise i will check it out & let ya know