Have posted questions before, thankful for this forum.
I just towed a friends E250 back to his shop. We have determined that the fuel pump operates when the key is turned from off to on but when you crank to start it stops pumping. Any advice would be great, thanks.

 

was this truck in a accident? if so id check the inertia shut off switch. also things to look into, the fuel pump relay itself. another thing is check for a faulty oil pressure sending unit. i have heard if there is a bad oil pressure sending unit or no oil pressure at all it will shut the fuel system down so that it wont start and run with no oil. hope you guys get it figured out good luck..