06' won't start... need guidance

Mudn_1

Mudn_1

Sweet Home
Joined
Apr 24, 2007
Messages
5,290
I have a customer with an 06' truck. It shut off when coming to a stop. He took it to another shop and they replaced CP3 and in tank pump with no dice.

Truck comes to me, checked RP and only building roughly 750psi of Rail pressure, Lift pump pressure 12-15 psi, rail relief valve capped with no change, removed and tested injectors which were out of spec, replaced injectors. checked grounds, batt terminals good. swapped RP sensor no change No Codes.... one thing is the RP sensor is jumping between 21 and 49psi with key on.

WTF am i missing?
 
Sounds like all that's left is a ecm or a short in the wiring maybe. What's it read if you unplug the rp sensor? Try unplugging the fca and see what it reads when cranking
 
Last edited:
Any codes?

Had a 08 6.7 that wouldn't start or run here one time... The fan had gotten into the fan clutch wiring harness which is tied into the crank sensor wiring. Replaced the fan clutch and installed a new harness and it ran like a champ
 
Unplugged Fan Clutch Wiring with no Change, FCA unplugged makes no change in what it builds.
 
4.95 On center pin of the sensor, 4.96 on the left.
FCA shows 7.55v

with just key on
 
with charging batts and removing solenoid for exhaust brake wiring it will build about 1100 psi RP and drops straight to 300 then back up while turning over.
 
Swap in a known good PRV first.
No sense throwing new parts at it if you have good used ones to try.

Mark.
 
I've done a bottle test with the prv already with no fuel coming out.

Sent from my SM-G920V using Tapatalk
 
Did they tighten the nut for the new CP3? You have fuel to the CP3 but no pressure coming out.... bad CP3 from the box?
 
I don't know what a bottle test is. I do know that you need 1800 to 2200 psi cranking rail pressure to fire the injectors. I was off on the psi needed to fire. My bad. I just spoke with Todd at T&C diesel and he said to give him a call.
 
f6jbob said:
I don't know what a bottle test is. I do know that you need 1800 to 2200 psi cranking rail pressure to fire the injectors. I was off on the psi needed to fire. My bad. I just spoke with Todd at T&C diesel and he said to give him a call.
Click to expand...

Thanks. I Removed the pump and overnighted to Todd. I believe it might have been a bad pump out of the box. I have no idea where it came from, so Its hard to make the assumption of whether its a chinese or reman pump.
 
Pump was good. Back to the drawing board.

Sent from my SM-G920V using Tapatalk
 
You must log in or register to reply here.
Back
Top