I have a 97 F-350 4x4 powerstroke with 186000 miles no performance mods other than k&n intake. When i got the truck 6 months ago I put glow plugs and injector orings in it. Then about a month ago I was goin to work and it just fell on its face started smoking pure diesel smoke and the motor would almost die with it flat on the floor but after a sec it would clear up and run like a champ up to 2000 rpms and then all over again. So I tried to check the codes and my info side of my computer was dead so i could not pull codes so got a new computer. And codes said ipr sensor so replaced it and would not run put the old one back in and it would crank. so we hooked it to my brother inlaws computer from work (he works at a dealership) it said the hpop was putting out 250psi at cranking he said it needed 500 at cranking so I got bought a new hpop $880 later still wont crank. So it has new computer, ipr, icp,hpop,new oil change, new fuel filter,new glow plugs & relay,injector orings, and has almost new battries. all it will do is spin over. Any help will be great