Hi, My 19 yr old son just bought a one owner 1987 F250, 4sp, 2wd truck with 258K on the clock. The truck is in great shape for its age with zero body damage (no rust CA truck), good interior, new tires etc and he only paid 900.00 for it. The PO said that since new he has had the inj pump rebuilt 3 times, injectors 2 times and has replaced the block mounted lift pump 2 or 3 times. And, he removed the water separator years ago. The truck has been sitting for 4-5 yrs but fired right up after putting new batteries, fuel filter and 5 gals of new fuel in it. It will not however stay running when you try to drive it even though it idles real smooth. When you try to drive it, it quickly dies as you shift into 2nd gear and he usually has enough speed to let the clutch out and the momentum bump starts it but it dies again. Fuel lines/pumps/return lines etc are all clean and dry showing no signs of leaking. The mating surface of the fuel filter did show some signs of rust however..... I used a fuel pressure gauge on it tonight and it runs up to 5 psi after about 10 seconds of cranking but the gauge pulses from about 3.5 - 5 psi while cranking. I then checked the lift pump flow and got about 4-5 oz in 10 seconds. I have done some reading on this site and in anticipation of possibly needing both a lift pump and water separator, ordered the Facet pump/filter last night. While I wait for the pump, any other diagnostics I can do on this rig?