fred03Ram

Diagnosing hard cold start. Narrowed it down to low rail pressure when cold. After rail pressure rises truck cranks no problem. After cranking no smoke, no skip, truck runs great and will recrank immediately with no problem.
Injector return= 75ml/min
Rail relief valve= 0ml
cp3 pump return= 600ml/min (initially)
cp3 pump return= 100ml/min (after replacing w known good cascade valve)
all values while cranking 5sec at a time to a total of 20secx3.

After replacing cascade valve I reconnected the injector wires and truck fired on first try. I still had the return lines dumping in cups so I turned the truck right back off but noticed while cutting the truck off it sounded like the fuel was cutting out. Tried to recrank the truck with no success. Replaced the FCA with no change. In the process of replacing cp3 pump with a borrowed one.

Threw injector circuit malfunction codes on all 6 injectors after return volume test, but has not thrown any other codes.
My question is if swapping the cp3 pump does not fix the problem does anybody have any ideas of what else could be the problem? emc? I have the tool to block off each injector, but at 75ml/min is there any use? Dont have much faith in my local dealerships but im running out of things I can test and ideas. Any help much appreciated.

fred03Ram

Sorry 03 3500 SO with nv4500. 181000m stock aside from smarty currently at stock. #6 injector replaced at 64000 under warranty no other engine problems.