Help Cp3 issues?

[JRODS*LB7]

i just installed a lbz cp3 in my lb7 along with a brand new lbz reg. now my truck wont start!Truck ran fine before i took it apart just wasnt building enough rail pressure (example)desired was 23,000 actual 13,000 so i decided to change cp3,my injectors wer done about 12,000 miles ago,i double checked all the connectors i disconnected ,cracked the bleeder on the filt housing bled that!just cranks and cranks and cranks?I was told the cp3 i had bought only had about 30,000 on it? i know the reg is brandnew for sure and is humming when key on! Any suggestions?

 

[TeaBagger2006]

keep cranking.....its taken bout 15 minutes of cranking sometimes before they start when you mess with the fuel system. double check your connections

 

[JoshH]

I've never had it take quite 15 minutes, but I have had to crank several 30 second cycles before it will finally fire. How long have you been cranking on it?

 

[PAT]

Mine took 2 cycles of ~30 seconds each before it started. Gotta give it time to let all the air out.

Check connections again.

If that doesnt work...Do you have efi live? If so, log what your truck says while cranking. Do you have rail psi? It won't fire until you have 1500 psi or more.

 

[super diesel]

If you still have the stock filter/plunger, be sure to pump it 60-80 times then pump it or have someone pump it while you cranking it over and keep pumping it for about 15-20 sec after it fires. I've always had mine start up right away when doing it like this.

 

[PAT]

If you still have the stock filter/plunger, be sure to pump it 60-80 times then pump it or have someone pump it while you cranking it over and keep pumping it for about 15-20 sec after it fires. I've always had mine start up right away when doing it like this.

60-80 times!?????? lol I just crack the screw and turn the lift pump on. But I'm lazy.

 

[JRODS*LB7]

i never cranked it in 30 sec. cycles maybe 10 to 15 at the most

 

[JustinD]

Crank til it starts. Mine took a while when I took it all apart too.

 

[JRODS*LB7]

hey whats up man. yeah i double checked all connections kept priming the heck out of it ive cranked it about 10 times in 10-15 sec cycles

 

[Harbin_22]

Do you have EFI?

 

[JRODS*LB7]

Do you have EFI?

yep

 

[Harbin_22]

Have you monitored RP while cranking

 

[JRODS*LB7]

Have you monitored RP while cranking

no i havent (rp) reg pressure? sorry im new to efi

 

[Harbin_22]

Sorry fuel rail pressure. Have the PIDS desired pressure and actual pressure on. Desired should be 5,000+ and the actual needs to be 1500+ during cranking

 

[JRODS*LB7]

Sorry fuel rail pressure. Have the PIDS desired pressure and actual pressure on. Desired should be 5,000+ and the actual needs to be 1500+ during cranking

ok i will check that

 

[super diesel]

60-80 times!?????? lol I just crack the screw and turn the lift pump on. But I'm lazy.

Opps! Oh yea. I see he has an Airdog. Didn't notice this. Shouldn't need ANY pumping with the lift pump on.

 

[JRODS*LB7]

desired while cranking is 6300 actual 242 psi....??????????? wtf!

 

[PAT]

If you don't see 1500psi while cranking, your truck will not fire the injectors. Thus truck won't start.

You can crack the banjo bolt open on the ficm and see if you have fuel going to the cp3. Just don't crack it to much or fuel will go EVERYWHERE when the lift pump turns on.

 

[JRODS*LB7]

ok gys i pulled the hose off the cp3 inlet and i got pure fuel no air going to cp3...then i cracked the outlet line barely any fuel coming out...?

 

[JRODS*LB7]

put my finger on the outlet of the cp3 while cranking i got nada i get more outta my old cp3 spining the pump by hand