Engine/Transmission (1998.5 - 2002) vp 44

[cmills]

Hey everyone, my truck runs great most of the time, except for a rough idle every now and then. But now when I go to start it after it is already been ran and is all warmed up I have to crank it a lot longer than I used too, it starts great in the morning or after it has set for several hours. I checked the lift pump pressure and it is good and the truck runs fine after it is started.



So is the problem the vp 44 or am I missing something?

If it is the vp 44 how much is a replacement and am I better off getting a new one or a re-man?



thanks,



Cory

 

[kbond]

Originally posted by cmills

Hey everyone, my truck runs great most of the time, except for a rough idle every now and then. But now when I go to start it after it is already been ran and is all warmed up I have to crank it a lot longer than I used too, it starts great in the morning or after it has set for several hours. I checked the lift pump pressure and it is good and the truck runs fine after it is started.



So is the problem the vp 44 or am I missing something?

If it is the vp 44 how much is a replacement and am I better off getting a new one or a re-man?



thanks,



Cory

I had something similar to what you are experiencing. Turned out to be an intake manifold leak. Would especially make hard starts after it was warmed up. Anyway, I found the leak while checking for boost leaks pre-intercooler.



-Ken

 

[cmills]

thanks Ken, but I don't think that is the problem because I have normal boost levels according to the guage, and the last time I blew a intercooler hose off I could hear it .



Anybody else have any other ideas?







Thanks,



Cory

 

[RobertMiller1]

sensor

Curtis had a similar problem. wound up being his crank sensor i believe.

 

[rweis]

fp gauges?



We had a SouthEast TDR meeting at SouthEast Power Systems in Tampa today. They talked all morning about the VP and the fact it MUST ABSOLUTELY MUST have positive pressure under ALL circumstances or it is toast.



They rebuild VP's. BTW Bosch has NOT released the final software for the Bosch machine that test and calibrates the VP's. Supposedly by November. They are really good rebuilding pumps injectors etc and know what they are talking about.



I would first make sure positive fp.



Bob Weis

 

[KWIKKURT]

Originally posted by cmills

thanks Ken, but I don't think that is the problem because I have normal boost levels according to the guage, and the last time I blew a intercooler hose off I could hear it .



Anybody else have any other ideas?







Thanks,



Cory

Cory, You can have a HUGE leak and still maintain boost levels. Kurt

 

[reddge]

Cory,

Do you have a pusher pump? I have the same problem after insulting pusher pump. The VP do’s not like high-pressure at start. I put an on off switch on the pusher pump this cured the problem.

I talked to Cummins engineers; they said it would be OK. The VP should not have any problem running at 20 to 25 psi.

PS.

This switch works like a theft deterrent also.

 

[cmills]

Reddge,





I do have a pusher pump on mine which I have had for the past 60,000 miles and it has always been a little harder to start since the pump was installed but it has gotten a lot worse in the past couple of weeks, and like I said before it starts pretty good when it is cold, it is when it is already warmed up that I have a hard time starting it. I also just replaced the crank pos. sensor a few thousand miles ago.







Thanks,



Cory Any other Ideas?

 

[cmills]

I just read a post that tgbol wrote and he said that his vp 44 was going bad and named one of the symptoms as hard starting when Hot does this mean that mine is going bad then also? If so how come it is hard to start hot but not when it is cold?



Thanks,



Cory

 

[Mad Bomber]

BigBob had the same thing happen it was the injection pump

 

[reddge]

YES CORY,

Like I said, I have the same problem. It did not start right away

and it only starts hard sometimes, and only when it is hot.

Give it a try next time its hard to start. Disconnect the pusher pump, it will start right up.

Your PV44 is OK.

 

[BatMan01]

Re: VP44

Is your pusher pump power triggered by the ECM or connected directly to 12v? I have been running the Enterprise pusher pump kit for about 40k now and it is setup to only allow minimal presure during intial key on. I have never had problems starting on first crank hot or cold. If you are setup this way and you find that bypassing your pusher pump (as suggested above) cures the problem means that there some VP44's out there that are can not handle the 20 + psi Cummins is saying they can. Let us know what you find out...

 

[Steve Campbell]

I would......

start with the "cheapest/simplest" ideas (as given above) and work up in price/time from there.

 

[cmills]

My pusher pump came from Enterprise engine also, Mine is hooked up straight 12v comes on right with the stock lift pump. but like I said it has always been a little hard to start with the pusher pump but why would it all the sudden get real bad all the sudden?





Cory

 

[jmadden]

hopefully it's not time for you to do the new vp thing, but should you find yourself doing a vp44 replacement... the cheapest place anyone seems to have found is at:



http://www.cumminsstuff.com



$750 for the vp plus a $250 core charge.



jm