So I'm pretty sure I have a a cP3 problem:

No power to the point to downshifts on hills and the rpm shoot over 3k
Horrible diesel mileage ~10
P1093/P1904 codes

I would like to check my fuel rail pressure before I purchase a new pump thought, but based on the symptoms do you all agree its probably the CP3?

This brings me to my next question, the truck is really used mostly for a daily driver and for towing and hauling trailers and I plan on keeping it for a while so you all think I should I purchase a new, reman, or modified CP3? And who do you recommend I purchase it from. Thanks!

What about injectors or a fuel filter?

Also, there is no P1904 code. You sure it's not a P1094?

Im having the same problem. 2002 duramax 2500. It doesnt have white smoke at idle or fuel in the crankcase. So Im thinking mine is the pump too. It has been steadily getting worse over the course of a few months. How did you get your codes?

Im having the same problem. 2002 duramax 2500. It doesnt have white smoke at idle or fuel in the crankcase. So Im thinking mine is the pump too. It has been steadily getting worse over the course of a few months. How did you get your codes?

White smoke and fuel in the crankcase aren't the only injector problems. They can bleed fuel pressure. Pumps can also fail and build little pressure also.

Shookme: My bad I meant P1094. Also I have changed the fuel filter with no effect.
Gorilla64: I used a craftsman OBDII scanner I have, the codes popped right up when I viewed current extended DTCs.