So I blew head gasket in my 05 2500 lly. I bought a wrecked truck and decided to just swap engines. They both ran but the guy I got the good engine from said he thought the cp3 may be acting up it had died a few times or whatever but still ran. I drive my truck into garage and changed engines. But I changed the cp3 when I had engine out just to be safe. He said injectors and head gaskets and studs only had about 8000 miles on them and studs all looked like recently done. Anyways I get it in and can’t get it to prime the rails. Fuel just trickles out. I rebuilt primer changed cp3 again and still the same no pressure. I got pissed unhooked glow plugs and sprayed it. It started and I happened to have the crossover fuel line to passenger side rail cracked and when it started fuel sprayed like crazy like finally I thought it busted that air or whatever out and finally primed. Try to start it again with no spray and same crap fuel hardly trickles out of injector line. I even thought it wasn’t spinning fast enough so I got a new starter and two new batteries. I’m so lost I can’t figure this out. Any ideas?? I’m desperate it is my plow truck and it’s supposed to snow tomorrow I really need my truck.