Engine/Transmission (1998.5 - 2002) what actually happens when the VP44 goes bad

[emarsh]

do they completely seize up? or do they gradually lose output pressure until they cause driveability problems?

More correctly, what breaks or wears out inside, either mechanically or electrically

 

[JLandry]

From what I've read, they can seize up if abused badly enough (fuel contamination and internal rust) but they rarely do. They usually seem to fail rather suddenly from several other causes...

• The on board computer can fail outright.
• Wear occurs in the injection advance mechanism and pump housing so the required injection advance can't be achieved, which in turn triggers a P0216 DTC.
• The injection solenoid can fail.
• The accumulator diaphragm ruptures.

There are probably a half dozen other ways it can fail, but going from memory, the above are the most common. The VP44 is quite a complicated but amazing piece of equipment.

Regards,

John L.

 

[BILLVO]

If it is symptoms you are looking for



Surging

dead pedal

hard start

no start

surging with cruise on

hard start after operating temps are hot but starts normal when cold.

engine misses or stutters at idle or unloaded when hot

 

[Rattler]

The electronics crapped out on mine:{:{, but they had 194K on them when it happened. Randy

 

[jeepit]

The electronics crapped out on mine:{:{, but they had 194K on them when it happened. Randy

That was a long life!!

 

[Rattler]

Yes but i still hated to shell out the money for a new pump. Randy

 

[Chief USA]

Probably not much help now, but it is a good worthy read:



Blue Chip Diesel Performance Specialists



Blue Chip Diesel Performance Specialists

 

[emarsh]

Thanks, I do not hear the VP coming on, I even jumpered the relay and all I get is a slight click sound. This also while cranking engine. The VP44 is the weakness in the cumings product. I only have 44 k miles on this truck. It sure has been a disapointment. Maybe thats why they call it a vp 44; they only last 44k miles!

This thing was running perfect, then it was parked and would not restart.

 

[georgej]

I'm not sure you'll hear the VP come on when the ignition switch is turned on,That's the lift pump which feeds fuel at 5 to 15 psi (hopefully). If the lift pump isn't putting out proper pressure and flow that will shorten the life of the vp. Use a pressure gauge hooked up to the schrader connection at the fuel filter canister or inlet to the vp and see if there is pressure. Either start the engine or bump the start position on the ignition switch and the pump should run for 30 seconds or so...

 

[JCyrbok]

yep the VP44 does not run if the engine is not running (atleast in the 8 years of owning a 01, I have never seen that). Its timed off the of front gear train and I doubt that it would run if it is not getting the timing signal (not positive about that though). The LP will run with a key bump for 20-25 seconds.



The VP is a decent injection pump its the LP that craps out and kills the VP because it is lubed/cooled by fuel. The LP goes out and eventually kills the VP from lack of fuel flow, if you do not have a fuel pressure gauge you dont know until its too late. . Happened on my truck at 45k (after 4 total LP failures it was still running but had pretty bad dead pedal) but I have over

60k now with the replacement and with a FASS pump, not a single hiccup.



Most common failure of the VP from what I can tell is the electronics that are on top of the pump die from getting too hot and there are internal failures (cracked diaphram) from lack of fuel. Like any mechanical item there is a certian number that are just **** right out of the box.



Most common symtoms of a dying VP44 are: dead pedal while driveing, code 0216, hard starts with a hot engine, reduced mileage and power and ending with complete failure. I was able to get about 1. 5 years out of my VP after I started getting dead pedal and code 0216 until it became too much of a pain in the rear.



Hope this helps

J-

 

[blacksheepdiesel]

emarsh,

Have you tried testing the VP44? Follow the test lead hook ups in post #4 of this thread https://www.turbodieselregister.com...nsmission-1998-5-2002/74018-testing-vp44.html

Godspeed,
Trent

 

[MKreiberg]

252,000 on mine. Its getting replaced this weekend. Still running, but not running right: rough idle, intermittent miss, hard start (started last sat on two-ish cylinders).



Do I tap the wire from minute one or not ? :-laf

 

[stg2500]

Mine had 240k when it died. Several times had a dead pedal then died at the top of the driveway. Had MassDiesel put in a pump with an extra 100 HP. Nice modification

 

[emarsh]

my truck only has 44 k original miles, this will be the second VP44; all I have is a edge fuel box.