I have a 94 Powerstroke 7.3 and I have recently done a fuel bowl delete as well as installed an electric fuel pump. At idle the fuel pressure is over 60-65 psi, after driving approximately a mile the truck dies due to lack of fuel pressure. I can immediately turn the key to the on position and it builds up fuel pressure and starts right back up and is good for approximately another mile or so. There are no obvious leaks in the fuel system. When parked overnight the truck had 20 psi on the fuel system and this morning I checked and it still had 20 psi on the gauge about 12 hours holding pressure. Any ideas of what could be causing this loss of pressure when running??