The fuel system on the Ford Power Stroke engines is designed to function properly with the factory programming. By altering the factory programming, more fuel is used and possibly at a quicker rate than what the fuel system was designed for. This can cause tremendous problems for the injectors. There are quite a few moving parts within each injector and running them dry will cause eventual malfunction and failure.
The problem lies with the basic design of the system. The factory fuel system works like this: the fuel is pulled from the tank and sent through a 10 micron fuel filter and then to the fuel pump, which is located inside of the fuel rail. The fuel pump then sends the fuel up to the front of the engine. There, the fuel enters into the second fuel filter housing. On the side of this housing is a fuel pressure regulator that is set to 60 psi, plus or minus 5 psi. Once the fuel pressure has been equalized, the fuel is then filtered by the second fuel filter (4 micron) and sent into each cylinder head individually. There is a fuel rail built inside of each cylinder head. The fuel enters from the front and it dead ends at the back. There are small ports inside of the fuel rail for each fuel injector.