Back in the day when these trucks were new (and I think limited to 2001 models) the rolling idle flow chart was this:

1) Rolling idle cold= software
2) Rolling idle warm= regulator

Now all of this should be old news and the model year does not fit, but I would also be looking at the fuel filter and say that you need a lift pump. The CP3 has been known to last seemingly forever.

My other thought which is the most likely is the source of the reman pump. I see LOT of sub standard stuff especially if "reman" by anybody other than Bosch Factory. I won't name names, but I suspect the answer will be coming soon.

More reading on lift pumps: http://www.kennedydiesel.com/docs/Du...ift%20pump.pdf