Installing a VP-44 in a 1999 Dodge Cummins Duallie
This article is in 3 parts.
1. What happened and diagnosis
2. Installation of the pump
3. Observations after the install
I was simply driving down the street about 40 mph with no
load and the motor just quit. There was absolutely no warning, no dead pedal,
misfire, or hesitation.There had been
no leadups to this that were noticed. The truck had good power and was
responsive. We had been on the new ULSD for about a month and there was full
winter fuel in effect. Minn has
2% biodiesel for about a year so there was 2% bio in the tank. No problems
related to this so far. The mileage had dropped off about 3-4 mpg but I had
considered this normal for winter weather. The night was cold at about 25 deg
F.After pulling over to the side of the
road I tried to restart. The motor turned over as normal (see later starter
replace) but there was no indication of firing.The truck had about 163k showing and the pump was the original. One lift
pump was replaced at 105k. When the VP-44 failed, it was showing 14 psi after
My son brought his scanner over and we found 2 codes.1689 no communication to fuel module, and 336
crankshaft position sensor fault. Both of these codes were repeated twice.Both of these are pretty much classic VP-44
failure codes.As it turns out we tried
to clear the codes and see if they would reappear during cranking.The truck system kicked the scanner off line
which was the first time my son had seen this. We tried again and the same
thing happened.Can’t explain this.We easily cleared the codes with the new pump
I posted on DRT and got immediate help. IEreplace the VP-44. No doubt.
We called about 12 different dealers and truck shops or
repair people. All said the crankshaft position sensor was bad. So we agreed on
that.One tech said he had seen a “tone
ring” that had fallen off. Most had never heard of it. All 4 of the dealers
wanted the truck brought over to run on
their scanner. ($100-120) They all initially though it was the ECMwith exception of one of the tech who agreed
that the pump had failed.Quotes for the
repair went from 2850 plus about 400 for the in tank lift pump to just over
$3000 plus the lift pump. There would be no warrantee with out the intank
pump.None would remove the new ECM if
it turned out not to be the problem.
The diesel tech and shops were about split on ECM and
Injector pump. None offered any additional help as far as diagnosis except
bring it in.One guy did bring his Snap
On scanner over and it further broke down the 1689 code to no communication
between the ECM and the injector pump module.A lengthy disagreement on whether this was replaceable or not
resulted.I finally convinced him it was
not something that could be bought over the parts counter.With that he agreed that the only option was
to replace the VP-44 even though he felt that it was the electronic module was
bad and not the mechanics of the pump.He
was the only one that seemed to know what he was talking about. Perhaps a
little too much what was failed and not enough on the repair part.I would have let him do the job as he said I
could get my own pump and as long as the lift pump was good he was ok with it
but I couldn’t wait 2 weeks.I decided
to do this myself with my son helping.As it turned out my son did most of the work while I either watched or
chased tools and took pictures. Nice to have a talented son.
As a side note, When we had finished installing the pump, we
went to start it and the motor turned over about 1 turn and the starter went up
in smoke.Since I had purchased a
Lifetime starter from AZ I did the R & R as noted below.AZ was very good about replacing the unit.
Glad it didn’t happen out in the country however.
Replacing the VP-44
It was about 40 degrees out side so it was a little cool. We
gathered the tools according to posts on DTR and laid them out on a big piece
of card board.We went over to Harbor
Freight and purchased a set of metric crowfoot line wrenches mostly for the
19mm one.We also went to Sears and got
a ¾ combination wrench in stubby style, a ¾ - 5/8 line wrench, a 24mm and a 27
mm 12 point ½ in drive sockets.Then we
went over to Auto Zone and got the crankshaft position sensor and a steering
It would not be a bad idea to put a new camshaft sensor in
too as they are about $45 -65 but entail removing the injector pump to install.
I got this pump from Midwest Fuel injection. Great to work
with.I had it the next day andthey don’t charge for the core charge for 30
days so you don’t have to front that money. They also pay for return shipping.
I laid out all the tools again:
10mm 12 pt combination wrench
¾ x 5/8 line wrench
¾ 12 pt stubby combination wrench
19mm crowfoot line wrench
24 mm 12 pt ½ drive socket
27 mm 12 pt ½ drive socket
set of metric hex drivers 3/8 drive
set of metric Torx drivers
set ofmetric sockets
12 pt 3/8 drive
set of metric deep wall sockets 12 pt 3/8 drive
socket set from a serpentine belt tool. These are optional
but the sockets are 12 pt and ultra short.I used one of them to get at the injector pump to front cover nuts
8 inch 3/8 extension, a wobble extension is even better.
3 inch 3/8 wobble extension
3/8 standard ratchet
3/8 “flop head” ratchet
½” drive breaker bar.
Phillips screw driver
Standard screw driver medium
Steering wheel puller (straight)
REMOVING THE PUMP
Disconnect both batteries
Remove the dipstick tube bracket from the air horn
Remove the flex hose from the air horn to intercooler. Place
a clean rag in it.
Remove the 4 bolts on the air horn and the nuts for the
wires to the grid heaters.
Remove the air horn and grid heaters. Be careful of the
gaskets so you can reuse them. Place a clean rag in the manifold opening
Remove the fuel line from the pump to the filter.Be careful of the gaskets.
Remove the fuel return line at the pump. Be careful of the
Remove the plastic housing over the top of the fuel pump.
Remove the bolts holding the APPS sensor on and swing it
over to the fender. Best to tie it off with the dipstick.
Disconnect the 9 pin connector from the pump
Remove the injector lines 1,2,3 from the head. DO NOT REMOVE
THE BRACKETS HOLDING THE LINES TOGETHER. Set these aside on your bench
Remove the matching line nuts from the injector pump.
Remove the engine lifting lug from the head.
Remove the injector lines 4,5,6 from the head. Here is where
the 19mm crow foot line wrench is needed.
AGAIN DO NOT REMOVE THE BRACKETS HOLDING THE LINES TOGETHER.
Remove the injector lines 4,5,6 from the pump and set aside.
Remove the bracket at the rear of the pump that attaches to
Remove the breather tube and housing. A strap wrench works
well but muscle works too. It just screws into the front cover.
Bar the motor over using the 24 mm socket in the alternator.
You can only turn the motor over one way and slowly.Use the mirror to watch for the line up marks
on the pump gear. Align these so they are straight up or .The key
way must be at or you will
drop the key into the gears. Don’t do this!!!
Loosen the pump drive nut with the 27 mm socket. It’s tight
but not impossible
Remove nut and washer from the front of the pump.We stuck a small magnet against the pump
shaft, then slid the nut and washer onto the magnet stem.
Install the small wheel puller using the bolts from the air
horn. We had a hard time with these as there is thread sealant on the threads
and it felt like the thread pitch was wrong.I think the gear in the motor had the threads very tight probably from
heat treating the gear. Since these are for us mechanics to use and not for
production they probably are not checked.The threads are the same but just tight. We finally used some soft bolts
we had laying around. The puller will pop the shaft loose very easily.
Remove the puller
Remove the 4 nuts holding the fuel pump to the front cover.
Use the long 3/8 extension on the lower 2
The pump is now loose but you must be very careful of the
key in the pump shaft.Wiggle the pump
until it breaks free. It’s mounted on a dowel pin so the pump must go about ¼
inch to the rear before you can turn it. Also be careful of the lower bracket
so it doesn’t get caught on anything. Slide it to the rear watching for the key.
It will remain in the shaft if you don’t bump it.Once the pump is clear you can set it aside.
There is a bit of fuel in the pump so don’t rest it on your lap until it is
Roll the pump over and remove the lower bracket. (150 Torx)
Inspect the bracket for cracks and damage. Replace it if necessary.This bracket is very important so don’t toss
Clean everything up and get ready to finish up.
The new pump comes with a new key specific to the pump. It
has markings on it so make sure they are in the correct direction.We removed the key and added some heavy
grease to the slot to hold the key in place and some grease on the o-ring to
aid in installing the pump. Some use super glue on the key, some use tape. The
grease worked for us.
Install the pump being very careful of the key. Use the
mirror to get things lined up. The dowel pin will guide the pump in.
Install the 4 pump housing nuts loosely.
Carefully install the washer and nut on the pump and snug
them up. Don’t tighten yet
Tighten the 4 pump housing nuts.
Install the support bracket to the pump and the block.We got at them from below.The object is to tighten them evenly against
the block and pump so there is no binding against the pump.
Now finish tightening the pump drive nut and washer.These are about 125 ft lbs
Reinstall the breather assembly.
From here it is the reverse of the disassembly.
Leave line 1, 3, and 4 slightly loose so you can bleed the
air from the system at startup.
Once everything is installed and tightened up you are ready
Make sure all the tools and other items are secure and out
of the way before starting.
Hook up the batteries
Turn the key on and bump the start but do not start it yet.
The lift pump should run for about 20-30 seconds.Do this 2-3 times to purge some of the air
out of the system.
Now crank the motor. It should start firing in a couple
turns or less.It will rumble and sound
terrible. As it starts running, you will see fuel coming out of the loose
lines.We shut it off at this point and
tightened up all the lines.Upon restart
it rattled and rumbled and blew out a dense cloud of smoke then after a minute
or so it started smoothing out. With about 5 minutes it was idling fine. We let
it run about 20 minutes before hitting the throttle at all.It responded great so we jumped in and went
for a ride.It was like a new truck!!!
WHEN THE MOTOR STARTS , DO NOT HIT THE THROTTLE JUST LET IT
After the motor has warmed up be sure to retighten the
injector lines.I got about 50 miles
down the road and washed the motor and entire bottom of the truck in diesel. It
took 2 stops before the lines were all sealed back up. A trip through the car
wash cleaned up underneath, but there won’t be any rust this year for sure. Be
sure to clear the codes at this point.
If you have all the tools ready, you should be able to do
this in 4 hours easy even on the ground outside.A good shop guy could do it in 2 hours and
have time for a break.
OBSERVATIONS AFTER THE INSTALL
The truck began running very well immediately after I got on
the road again.
I noticed a big improvement in low end torque. Where I used
to slip the clutch a little on starting out, it now just moves out by
itself.There is a marked improvement in
power from 1200 to 1800 rpm. It always seemed like the turbo was taking its
time spooling up in this range but not now.There were times when it would blow huge clouds of black smoke when
accelerating mostly when it was wet and very humid. It doesn’t do this
anymore.The idle down just as you are
coming to a stop is only about 100 rpm at most now where it was about 200 rpm
before.Sometimes it is not even there
now, usually when it is cold.It also
doesn’t drop rpm as quickly between gears so up shifting is much easier and quicker.
Starting is much improved. It was taking about 2-3 turns of the motor to get
started, now it doesn’t get 1 turn even at 5 deg F.
Summary of a failing VP-44 according to my observations
Gradually slower starts even with good batteries and
Hard starting when it is below 0 outside.
Gradual loss of power at low rpms
Gradual loss of MPG I had previously always gotten 20+ on
trips. It gradually became harder to maintain this, finally getting down to
about 16-17 even on easy trips.
Sometimes a gently rolling idle where it was dead smooth
Clouds of black smoke when briskly accelerating.It was very hard even to get a puff at any
time when the pump was good.
The motor slowed down sharply when shifting up. Now it is
easy to maintain rpm
I never noticed any “dead pedal” or limp mode but I did seem
to get less power on occasion. It was so slight and gradual decline that I
really didn’t take serious note of it.
Today the truck runs a good as new. It starts instantly even
when cold, I’m back up to 20 mpg even with ULSF and winter grade, The idle is
dead smooth, the power is way up and is doesn’t knock as much……Plus I have some
more tools to carry in the truck and knowledge in the head.
SIDE BAR ON REMOVING AND REPLACING THE STARTER AND
CRANKSHAFT POSITION SENSOR.
To remove the starter
Disconnect both batteries
Jack the truck up and set on jack stands.We also put it on 2 sets of 4 x 4 under the
front wheels.Block the rear wheels
front and rear.
I slid under it on a piece of cardboard this time.
Remove the big battery wire and the small solenoid wire.
Loosen the 2 lower bolts about a turn.
The top bolt is only accessible with a 10mm 12 pt
combination wrench. About 6 inches long.
I go under the truck on the left (driver) side and roll on
my side so I’m more or less facing the rear end. Using my right hand I can
reach up and over the rear of the starter and get the 12 pt end on the head of
the bolt.I have much more strength and
leverage even from this awkward position. It takes a mighty tug to get the bolt
loose the first time. I had to wrench it all the way out the first time.I’ve done the starter R&R 5 times
now.Once it is loose keep after it
until it is out. Then return to the bottom 2 bolts and remove the starter.It’s not real heavy.
The crankshaft position sensor is just ahead and behind the
starter and retained by one 10mm bolt.
Remove the wire connection and push aside.
Remove the 10 mm bolt.
Carefully wiggle the sensor until it pops out of the block.
I had to pry it a little. Don’t rush it and bust it off in the block.Also take your mirror and a flash light and
take a look in the block. You may be able to see the “tone ring” that the
sensor reads.If the sensor is damaged
on the block end…..well I hope your tone ring is good and still tight.
Clean the hole out and put a few drops of oil on the new
Pop it in the hole and replace the bolt. The bracket will
hold it at the correct depth.
Plug in the wire and you are done except for the starter.
Put the starter up in the hole and install the lower 2
bolts. I snug them up a little.
Then roll over facing the rear and wrap your hand around the
starter and install the top bolt.
Tighten the top bolt as tight as you can then finish off the
bottom 2 bolts.