Engine/Transmission (1998.5 - 2002) Truck Won't Start !

[DMechals]

Hey guy's Maybe you can help me out? I have a 2000 ram 2500. I'ts pretty much stock except for 4" exhaust. It has 142,000 miles on it, and about a year and a half ago I replaced the lift pump. Then another 6 months, the crank-speed sensor. Well, Iwent out the other day and it wouldn't start. I'ts showing a P1693 code. My friend say's injector pump,fass,and a fuel pressure guage is where he would start. anyone else got any ideas? I'm new to diesel trucks' so please speak slowly. Any information on how to fix my truck,and avoid this in the future, are greatly appreciated. If it is an injector pump, are all rebuilds the same? Thanks, Waiting for help.