Its time to replace the CP3 on my 06 5.9 (235k miles / all original stock), rail pressures are low and drop on hard accelleration and never get over 20k psi.

It appears that everyone that can spell Diesel and CP3 have a new or re-manufactured offering.

Who are good and who should i stay away from ? Im leaning towards DAP for a new CP3 and maybe a new set of stock injectors but open

 

Are you sure it's not the FCA that's crapping out or your fuel pump? I have heard those commonly going bad vs. CP3s. I have done both of mine and I just rolled over to 236k

DAP is a great resource- I purchased my injectors and turbo from there- let them know you're on this forum and they may be able to help with pricing

 

Replaced the lift pump 2 weeks ago and it got a little better, the FCA last week and the pressure got a lot more stable.

not much left ... I'm going to pull the connection off the top of the rail pressure relief valve and see if it's leaking by there, and double check the rocker alley for a injector leak but I'm running out of possibilities.

what's jumping out at me is that I can be doing 70mph, 18k / 19k PSI, and step on it and it drops to 15k / 16k then slowly come back to only 19k.

 

Well there's not much left then! Definitely should not have an issue keeping up with stock fueling!