2001 Ram 3500 Cummins stock with Edge Attitude. Gradual loss of fuel pressure ove past 500 miles down to 3psi with light load. I cannot go over 55mph without the Edge alarm going off. 7-9 psi at idle.
- replaced fuel filter no improvement
- installed new FASS lift pump no improvement
- checked return pressure valve on VP44 and it seats and holds pressure.
I suspect an issue with the tank pickup or line to the lift pump. Have 3/4 tank of fuel in it.
Anyone ever have this symptom?