Well this is more of a follow up on my last thread but my truck is finally at the dealership and they starting looking it over today. I replaced all six of my injectors because of a no start/ low power problem. The truck now starts but will only fun for so long. It has no misses or knocking. Dealership mechanic called me back a little bit ago and said rail pressure was at 4800- 4900psi at start which is close to spec but as it runs it will slowly lose pressure. They are isolating the injectors now. Any thoughts of why im losing rail pressure? I wouldnt think the PRV would be an issue at such low pressures compared to wot rail pressure. Any help would greatly be appreciated.

Jordan

 

first thing i am thinking is crossover tubes not torqued and leaking fuel past. did it make fuel?

 

no fuel was present in the oil. Its idled for probably a total of 45 mins since the injectors have been replaced and no fuel has been evident so far.

 

Was rail pressure checked before injector swap? I never lost power when my injectors were failing but did have the hard start. It could be your CP3 was/is getting week? Did you ever upgrade the lift pump? Mine didn't make it 80K.

 

Rail pressure was not checked before injector swap. My bad injectors all flowed below stock spec with F1 40hp nozzles. Since the injector swap it now starts great but very low on power and will not idle once engine is warm. Ive talked to two mechanics at dealerships whom i know and they have only ever seen a handful of cp3's go bad on commonrails since 2003. Im not ruling that out yet but I had more power than I currently do before the injector swap. The liftpump is still on the side of the fuel cannister I was waiting to replace injectors before upgrading due to $$$. But the liftpump on it currently only has 35k miles.

Thanks,
Jordan

 

Sounds like the injectors need to come back out to inspect the copper seals and the o ring seals. However I have seen more than one truck idle pretty close to fine with a bad copper but they were low on power.

Have you tried to idle the truck with the fca unplugged while monitoring rail pressure?

 

Truck is fixed now. The #6 connector tube was the problem. They removed it and cleaned it and put it back in and all is good. Thanks for the help

 

The worst one to work around too!

 

Had the same issue but it took about 8 months for mine to loosen up. Truck actually ran great until a year later then I kept getting P0251 code. I finally broke down checked them all and 4 & 5 were loose, took about 4 to 5 quarter turns of the torque wrench to tighten them up.

 

yea #5&#6 are a pain. The fuel line on #6 almost made me crazy haha. Im a little green behind the ears though so I'll learn.