tmccar

Would anyone have a manual for a 2000 Pathfinder diesel pickup?

I have a 2000 Pathfinder with a .5L diesel engine. It loses power and revs after a few miles, and if I turn it off and start after a few seconds it fires up again and the revs come back slowly. I tried changing the plunger unit over the fuel filter but that didn't help. what else could it be?