rockbender
Full Access Member
Has pretty much everyone eliminated the return line that goes between the filter head and the #1 (or #4) injector cap? I'm having some classic air intrusion symptoms and am highly suspect that the lift pump check valve is not functioning correctly.
The return line system is open to the tank without any check valves, so if the check valve in the lift pump was not working AND the return line was hooked from the filter head to the injector return lines then that line easily provides a 'vent' for the system to back siphon through the lift pump and to the current equilibrium level of the fuel tank. Is my thought process accurate here?
Is there any good reason to leave the line from the filter head to the return lines, or should that just be eliminated? If I remember correctly, it seems that Ford actually put out a notice to eliminate this line.
The return line system is open to the tank without any check valves, so if the check valve in the lift pump was not working AND the return line was hooked from the filter head to the injector return lines then that line easily provides a 'vent' for the system to back siphon through the lift pump and to the current equilibrium level of the fuel tank. Is my thought process accurate here?
Is there any good reason to leave the line from the filter head to the return lines, or should that just be eliminated? If I remember correctly, it seems that Ford actually put out a notice to eliminate this line.