VP44 Injection Pump Teardown - How it Works

[@ToddKing]

19:11 VP44 pumps have offset keys, not keyways. The keyway is the slot in the shaft and the key gets inserted into the keyway. I'm not sure why but a lot of people call the key a keyway so you're not alone. 🙂 I've made a similar comment on several pump videos.

[@tommyduris3044]

Wow this is by far the best video out there describing the whole process in depth, Thanks Zac. Subscribed straight away. Great presentation, with heaps of technical info step by step. Awesome! I repair mostly VAG car audi, vw, skoda and seat and currently have an 2005 A4 B7 Avant 2.5 TDI BDG with what I suspect has intermittent problems with the control module on the 059130106KX injection pump. Car is chocking a bit on light acceleration. Haven't done this job before but some other mechanic mates said it's not possible to change the electronics and the control module. Looks like their so wrong hahaha After watching this vid will be doing the job myself and at the same time as changing the control module will also change all the rings and recondition the pump. Car has about 120k miles roughly so will be good. Thanks heaps again Zac for taking the time to make this vid and cheers boys!

[@martinpowlette9370]

Thanks guys, that really helps our diagnosis. We have a crank and no start on a Freightliner canteen truck. We substituted the dead lift pump with a universal inline pump just for diagnosis but fuel doesn't get to 1 & 2 during the bleeding and still no start. I gather lift pressure maybe 14psi or thereabouts so now I am suspecting or rather prefer we stick the correct lift pump to ensure good pressure and volume before condemning the VP44. What do u suggest for a good deadhead pressure tester ??

[@outbackenduro7418]

Explaining this pump the way you did was a great job and so helpful .... thank you very much

[@luke6030]

so hot rod or ho cam plate and the plungers from a so. would make a neat vp pump

[@bradryan8415]

Hey legends, awesome video and great explanation. Question, I have a Ford transit 2.4lt and fuel pump is leaking out of the front from ball bearing on the vane pump section. Causes and fixes?

[@bigdiffas]

Cool video! i have audi 2.5tdi compoundturbo v6 with vp44 running pretty decent power with 400+ with stock 2plunger pump head. It is now running 2x7mm plunger and 1550bar output pressure. I just send my other pump for pump head upgrade. It had stock 3x6mm plungers and that has 1850bar output pressure. It will recieve 3x7mm plungers i believe from cummins, but not sure. It should kick pressure and fuel quantity up. I've used 1.2-1.4bar 150gph lift pump and that should be enough?

[@misterapocalypse1]

Would be interested who mods these pumps, and how a 2-plunger head runs a v6? (wouldn't it need to be timed to compress fuel each "ignition" event?) I've got a 4cyl Nissan zd30 with a max VP44 output of 84/1000.

[@bigdiffas]

@@misterapocalypse1 most audi v6 have 2 plunger pumps. It is all about the camring inside the pump so timing is not a problem.

[@misterapocalypse1]

@@bigdiffas Interesting. Might have to look into pump mods for mine, I imagine even the larger plungers from a cummins would be useful in a 3L for more fuel. Who mods your pumps? Does it require PSG re-coding or just adjust the fuelling rate in the car ECU?

[@raulortega9468]

Great info!!!! Thank you for putting it out here!!! Now, quick question, im having an oil -diesel mix on my 01 24v, and took the injectors out and had it tested and came back good, now i just took that vp44 out from my engine on hopes that it would have a seal or something that's causing a leak of fuel in to the engine..... Is it possible???

[@savagefabrication795]

Awesome vid. I think I may be able to extrapolate my question from a screen shot of the injection lift cam but you may already have the answer to my question. On our chassis dyno we have noticed something really interesting between the different injection pumps, if each pump is limited to say 300cc of fuel min, we will get three different hp numbers on each injection system due to the brake specific fuel consumption ratio being drastically different and given all things are equal timing wise injector wise, this difference seems to be rooted in the injection duration in crank degrees. The ve and vp’s with their extremely fast injection duration in comparison too a p7100 seems to hold consistent that the shorter duration’s provide a better bsfc ratio. I have found pretty consistent data that at full rack a p7100 has about 29* of crank angle for a complete injection event, 11-12mm of plunger lift. The vp with the three individual 7.5mm plungers and I believe 3.7mm of plunger lift on face value seems to have much less injection duration then the p7100’s 29* but I have not been able to find any data on actual numbers. So I was curious if you have the data or can get that measurement? It would be extremely helpful in further understanding the injection event itself between the different injection systems :) thank you again. And awesome video.

[@ZachU812]

Great observation, I’ve had the same theory for a while but haven’t mapped out the VP44 cam ring yet to confirm. It takes a special tool to do it. It comes down to rate of injection and for stock quantities I believe that a stock VP44 will have a faster rate of injection all other things equal. With that said the rate of injection can be increased a number of ways on the P7100s so it comes down to pump setup and how much you’re asking of each pump. I’ll dig into this a little more when I get the rest of the parts for the P7100 teardown video.

[@philipkuhn3188]

Thanks for that fantastic video. I am a diesel mechanic qualified 40 years ago. I am just getting into having to sort out a Ford Transit van with a 2.4 Duratorq motor. I have just changed motors and found that the interface on the back of the pump may need reprogramming as it wont fire up, but the electrics worked fine with the previous motor. Your video has helped a stack before I start getting into the guts of the pump. Any suggestions would be welcomed. Cheers.

[@jdillon8360]

The Ford version of the pump has the immobiliser built into the pump ECU. You may need a special Ford scan tool to reset all that information, as the pump/ engine / vehicle all need to talk to each other.

[@edhog]

The pumps are specific to application unfortunately, might need a new board.

[@Mr69barracuda]

You do a GREAT job! VERY informative. I am a Mechanic and this is the FIRST instructional vid i have ever sat through end to end. My only suggestion would be to slow your speech on description words. i know you are in a hurry to make the vid concise .. But you have a tendency to "Bumble" on keywords that cant be understood even when replayed (Only once in this vid. mostly referring to your 98.5-02 500hp+ block upgrade vid) and usually in the start of the vids. Other than that I think i will be subscribing. Keep up the awesomeness!

[@jamesrobb4928]

Very informative video. I am replacing my VP 44 and I might have messed up. Removed the old one, and sent it out to be rebuilt. Was returned stating not rebuidable. So ordered a new one. Upon recieving it, I see the drive keyway is in the top position, and the keyway on the old one is on bottom. Do I rotate the engine to align the keyway, or should I rotate the pump, till the keyway aligns with the drive gear ???

[@andrewthorn3693]

Just rotate the drive shaft of the pu.p so the keyway aligns with the slot in the gear on the truck

[@darrinstone49]

Have you tries the coated timming piston yet? Can you replace it without tearing the whole pump appart? Pollydyne coating add thickness to bearings ect so is it a really thin coating? Did you coat your own pin? Love to play around with a pump I have that started acting up & would limit power untill I let the rpm... then it would work fine for a little while unless I was towing. Thanks

[@nathantilton5629]

How did you get the tone wheel set back properly and where did you get piston coated and with what?

[@jimforsyth2.]

Good video . I would like a better understanding on how the solanoid functions . And timing solanoid functions like the what when and why thay do what thay do

[@engenhokas69]

Timing solenoid allows high pressure diesel into one side of the piston, pushing it as needed to rotate (advance) the pump, injecting diesel sooner. The back (fuel) solenoid turns diesel on and off very fast to injectors, basically only allowing the desired quantity through the pump into the engine. The other sensor is the pump internal RPM sensor, used to see pump RPM in ecu and compare to crank signal, also used to measure pump advance to make sure it's in the desired amount. VP37 has the same advance solenoid so it is interchangeable, also same pressure relief valve (pressure relief valve is calibrated TO THAT SPECIFIC PUMP" Do not switch it.

[@dancohick6953]

THANKS FOR THE BRAKEDOWN, I wanted to ask if { sea foam, or injector cleaner, or metrical marvel l} could free up the parts when the elec top cap off, let it soak for how long , without taking the pump out ,then put all the top parts back, and see if the pump may operate and pump fuel correctly

[@josecamacho8477]

Do you guys rebuilt the VP 44 pump

[@taylorbroadus1458]

I need to know what size bolt you used to remove the fuel solenoid on the back of the pump please.

[@BillyWilliams-d2e]

Cool

[@TheKcdub1000]

Freeking awesome video! Thank you! Very well spoken. I've bein wondering how the vp44 worked. By the way, What are signs of a bad diafram? My truck won't start when parked on a hill. Nose up. Over night. I'm wondering if its pulling air through a split diafram. Or a bad injector. I can not find where the air is coming from. Thanks.

[@ChipLogicRO]

Replace the return pipe that screws into the vp44(the small one with a ball on the end, i think its called check valve. Sorry but my technical terms in english are bad)

[@TheKcdub1000]

I am going to replace it with a new one and see if it makes a difference. I guess they are supposed to hold 10pounds before opening?

[@ChipLogicRO]

@@TheKcdub1000 i am not familiar with the ones on cummins engine but probably. on my audi (i have the same pump/ or something that looks exactly like it, and works exactly like it) and i had at one point exactly the same problem. took me a few weeks to figure it out.

[@TheKcdub1000]

@@ChipLogicRO ok rite on. I have already replaced all the line from tank to vp44 as the old line was cracked. I also replaced the fuel filter housing. That was leaking at the o ring. I hope the check valve fixes it.

[@TheKcdub1000]

Nope, new check valve and still won't start after parked nose up. Looks like injector o rings are next.

[@axemanjoe2945]

FINALLY!! Someone who actually explains how a VP44 works. So their is a bleed down port that allows the fuel to flow and cool the FPCM, even if the pressure isn't +14psi?? Also do I really need to add a lubricant because of ULSD, or do they add a lubricant already to the fuel that's good enough???

[@leroymclean7847]

Do you need to adjust the pump timing when installing a new pump?

[@ZachU812]

No, it’s all electronic. Just have to make sure the timing marks or timing key is lined up depending on the application

[@jdillon8360]

The timing is all set on the test bench (a very expensive piece of Bosch testing equipment). On some models the hub is tightened directly on to the taper of the drive shaft without any key in the keyway (interference fit), this is done at the pump shop. On other engines the timing is set with an offset key set into the keyway, and then the hub (also with a slot for the key) and driveshaft fit together on the engine or just before installing. There's no timing to set or adjust on the vehicle. As Zach said. Just thought I'd add a little more information for anyone who is curious.

[@vc4019]

As I understand, upon reassemble the distributor shaft has a flat spot and can be installed 180* opposite. Does the key way on the front shaft correspond with the flat spot on the distributor? I also wish there was info on the distributor break down as well.

[@rogerwalsberg]

Good video. But you didn't explain what varies the amount of fuel the pistons pump to the injectors?

[@nschelling6420]

So how does low or zero lift pump pressure affect the VP44?

[@johnnytiboni6745]

It starves the vp44 of fuel which cools the pump no fuel =hot over heated pump= that = toasted pump. Another main issue for injection pumps is water in the fuel water is terrible for injection pumps so lady's and gents drain your water In fuel filter and change your filters and make sure never let your diesel fuel get old and stale because diesel is hydroscopic like brake fluid that means it collects and absorbs water I always use lots of( diesel power service. Injector cleaner and cetane booster) every fill up and I never have a problem they also have a bottle for antigel and storing fuel

[@luyandamthiyane7692]

What's problem for the vp44 pump diesel is coming but pressure is law what reason

[@ilgvars7960]

Great video, thanks!

[@elvirvili166]

i have an audi a4 b7 2.5 tdi when engine is cold everything runs perfeclty but when it starts to warm up the esp light pops up and engine runs on rough iddle when i floor the gas pedal it goes away then after a short time starts again can you help me please ?

[@kennethschlabach]

What happens in the pump to cause three cylinder mode in cold weather?

[@GERntleMAN]

On a sidenote: PSG means Pumpen Steuergerät. It's a common short for any pump related ECU in Germany. Since it's a Bosch pump, the nomenclatur is german.

[@chilidog73]

Excellent video. Thank you. So there a fuel temp sensor? Then how do these Vp44's keep failing/burning up the electronics? You guys seem to be very knowledgeable about its operation. What can a person do to keep it from failing. My 2001 has had 3. That's ridiculous and expensive. I appreciate any info you can share.

[@danielterrian4027]

Maintain fuel pressure and they’ll last forever

[@axemanjoe2945]

A lot of people say to add two stroke oil or some lubricant to the diesel fuel but I've known a couple people whose vp44 lasted over 200,000 miles and still going strong with just an aftermarket lift pump that provides 14 + PSI and no additives. So I'm not necessarily sold on adding lubricant to the fuel myself because it adds up over time gets expensive. I think if you make sure the fuel pressure is good and you have a gauge so you can read it your pump should last a long time

[@chilidog73]

@@axemanjoe2945I appreciate the reply! Yeah I ended up adding an airdog lift pump that I got a really good deal on on ebay, brand new. I've been running that for a couple years now with no issues. It pushes about 17 psi, 14 at open throttle

[@Neilhusqvarna]

How would you know the timing is correct if you’ve removed the outer belt driven pulley

[@lesleyavery7166]

Could you please ad subtitles for the hearing impaired as this is a great video

[@thenicholsonsinohio771]

Can the PSG be purchased separately somewhere? Having a hard time finding a supplier…

[@joecorrie1]

So I hear that the computer gets hot and the pump fails? But there doesn’t seem to be a computer just a plug to some sensors and one solenoid, is it the solenoid that overheats? From what I see The bypassed fuel obviously keeps the pump cool and under low lift pump pressure it seems to be just pump failure? Anyway good video thanks for posting.

[@colinsmith6340]

That's one of the failure modes yes. The pump has to stay fully primed all the time and the diesel inside the pump keeps the electronics cool. If the electronics overheats it either breaks solder joints or actually causes the transistor controlling the solenoids to fail.

[@jkdamijan2623]

nice video there with much information.

[@darrinstone49]

Can you replace the timing piston or seals as a possible fix for dead pedal?

[@TheKcdub1000]

I dont think the crappy low sulfer diesel dose these pumps any favors either. If I under stand it correctly low sulfer diesel dose not have good lubracation properties. I'm running a additive that puts the lubrication back in the diesel fuel. For the injectors and pumps sake.

[@jdillon8360]

Good idea. Also fill up your tank before you go below 1/4 remaining. These pumps need lubrication and cool fuel from the tank. When you get down to a low amount of fuel all the fuel gets hot, remember it's circulating constantly from pump to tank and back again. Good luck.

[@alexwolf4603]

5-20% Biodiesel that most sell these days is probably best for lubrication but it's not good for long term storage. If you don't drive much just fill with regular and add 2cycle ashless oil 1 oz to a gallon, then it'll last for a little ng time sitting not used.

[@awake5006]

Respect!! By the way, I have a bmw e39 2.0d with this vp44 pump. Monday I've put wrong fuel means petrol instead diesel. 18 litres and I had max 2 litres in my tank... After 1 mile the engine stopped. After I clean everything tank.. Lined etc the car did start using spray, engine sound perfect, but is not accelerating at al is just keeping 750rpm... Do you know what can be wrong?

[@ZachU812]

When this happens to the Dodges we call it “dead pedal”, to make sure I like to use a scanner and monitor pedal position to make sure that pedal position changes. If that is the case you likely have a pump issue unfortunately.

[@awake5006]

@@ZachU812 most likely.... because what i've noticed when i press slowly, is feeling like is a 0,01% increasing rpm...but the weird part is that the rpm are 750 excatly

[@jdillon8360]

These pumps rely 100 percent on diesel for lubrication. Petrol doesn't lubricate as well, so there may be damage to bearings and other metal on metal parts inside the pump. Once the hardening is worn away from the feed pump vanes or timing piston, it's all downhill, even if you now are running on super clean diesel again. Take it to a pump repair shop and get them to put an exchange pump on your vehicle. That pump won't get any better.

[@flapjack7177]

Is there a vid rebuild?

[@rockmahina]

WHAT IS quantity adjuster (n146) ?

[@andrewklahold2880]

Why would my vp 44 pump be like stuck in full throttle position 22:46 , i cant even start my 5.9 it starts but bloats like crazy and wont start and run, i came to the conclusion from opening the injection lines that there is way to much fuel the pump is trying to inject oh and i have fuel coming to the injection lines from the main lift pump so what valve or any valve is stuck to cause this problem

[@eighthacremaker7129]

Great video. Thanks 👍

[@gopherdestroyer]

Very helpful, THANKS!!!

[@jimforsyth2.]

What type computer was attached to the pump in video . With the little pig tail harness

[@ranatauheed6100]

Sir how I can set the timing of this pump ?

[@valcic1993]

Where is put comparator for timing adjust?

[@elitetrucking1427]

Hi guys nice video but i was hoping to see the removal of the diaphragm that separate thefuel chambers

[@antonioeugenioabarca4105]

What is the cause of not contain fuel in the vp44 pump

[@hubertrobinson8825]

Great video I own an 02 dodge with the dead pedal syndrome it has been like that for some time and the code says cam position sensor and pedal position senor are bad what should I do get a new pump complete instead of having someone try to make repairs

[@jdillon8360]

Is it original pump? If so, probably due for a replacement. Don't know if "new" pumps are available from factory anymore, but a good pump room can supply you with a tested and verified exchange pump.

[@cph3459]

Check the APPS sensor

[@Tegritydiesel]

Does that shaft seal hold back high pressure fuel?

[@ZachU812]

Just case pressure I believe

[@nickwhite6717]

Yeah only case charge pressure so sub 80psi

[@gasamugove9487]

Great video I urgently need a truck d0836lf3 distributor type electronic version injection pump

[@phile5450]

Are you still replying about this video? I have changed my timing solinoid as I was advised that could very well be the reason my van sounded like a tractor but now I have a question about the pressure regulator. How would I know if the pressure regulator was not working correctly and why would I not have diesel coming back from the return pipe from the injectors? Many thanks for any advice possible.

[@tonystacey3347]

Mine sounded like a tractor - replaced pump - problem solved. It’s deffo the module, that component gets too hot and fries so it’s 50 quid for a module fix or 500 quid plus fitting for a new refurbed fuel pump.

[@cph3459]

So why cant the electronics simply be replaced? seems simple enough.

[@colinsmith6340]

They can be replaced, but has to be programmed to suit the individual pump as they vary internally mechanically due to tolerances.

[@FulgencioMarcos]

Awesome job!

[@erickhechizo5738]

great video please keep them coming

[@edzgarage]

Thanks for the comment! More to come soon.

[@javiergonzaleztoledo]

I have a problem with my vp44 it just clicks when I hot wire the pump + , - also connected with the regular harness just clicks and has code p0215. I need an avise of how can I fix this

[@markohakkinen6715]

Great video! Any hint how to prime pump after this complete teardown?

[@valcic1993]

How you assambly back?

[@mr.noir98]

really reminds me of a cav pump

[@MyJeremy79]

My 02 cummins getting the death code intermittent. Now I'm having long cranking after warm up after it sits for awhile.does that mean my vp44 Goin bad. O I keep eye on my lift pump Maki g sure it always working. I got it 20 psi. My trk got almost 400 thousand miles on to to...

[@axemanjoe2945]

400k is really really good lifetime. Is it the original vp??

[@m0peds]

is the fuel soleniod a spill control valve?

[@colinsmith6340]

Kinda yes. It opens when the injection event is to be ended, spilling the excess diesel back into the pump itself.

[@m0peds]

@@colinsmith6340 yes I’ve had some experience with spill control valve in 3C Toyota, very nice setup without the expensive piezoelectric injectors

[@larsdoityourself3483]

Add 2t oil in diesel is to add lubrication to the vp?

[@axemanjoe2945]

You can add 2stroke ashless. I've known 2 separate people who never added any lubricant and have over 200k on their vp44. They both did replace the stock lift pump for one that puts out +14psi and gauge to monitor the pressure. The biggest problem with stock lift pumps are #1 they have no gauge to show the psi. #2 block mounted so the vibration causes the pump over time to get weaker and the psi drops and starves the VP44 but the driver doesn't realize because there is no symptoms. So the VP44 over time goes bad.

[@MrYeager1989]

My vp44 has an entirely different computer setup on it was wondering what this pump is off of

[@ZachU812]

This pump had the computer ripped off so it could be used for a project.

[@crazedgoldminner7384]

This one died at 70 miles per hour it's clear that we've lost the pressure at the injectors I ain't got enough up there I can pee harder all the electronics work it will not run with the breakout box no pressure to injectors so what is the most likely part of that injector pump to take a dive like that

[@jaredhamilton3231]

Do you need the correct key

[@jdillon8360]

Yes, the original key that came with the pump. It will have an offset. If you lose it or take it out and put back in 180 degrees around your timing will be out. Any good pump shop can check the timing, they have special tools and don't even need to run the pump on the test bench.

[@fiddlinjazz]

Any idea whats causing dead pedal?

[@alexwolf4603]

What he said or a bad apps sensor, get a timbo one not original, just Google timbo apps.

[@meldeer6253]

please dont kick me .. VP44 mine through a code the macanic said that usly meens the pump is about to shit.. that was a yr ago .. still running i put 100 hp injectors in now my fuel psi gage is acting like a slow tack odometer what is usly the most commen parts to replace or rebuild these.i understand inviroment is like a doctors operating room.. but when you get this apart what about timing issues with parts in side this thing.. hope that was not to many stupid question.it all looks stright forward.. iv all so been a machinest most of my life . and fabricator thank you

[@cephassibanda4019]

if you install a new vp 44 pump for audi 2,5tdi v6 ,is it a plug and play or it requires coding

[@bigdiffas]

If you have correct pump for your engine then it is plug and play.

[@cephassibanda4019]

@@bigdiffas I installed from another car, but not starting

[@bigdiffas]

@@cephassibanda4019 But is it same engine and same pump? Usually you need to go authorized dealer and make coding right

[@DrZoidbergism]

What on this pump dies when running it dry?

[@jdillon8360]

A lot. No fuel means no lubrication. All sorts of nasty stuff happens inside. Pump overhaul required usually.

[@DrZoidbergism]

@@jdillon8360 yea but I have this pump which is possibly broken and missing the controller. But I wanted to see if I can use it for spare parts in case mine fails. This is why I wanted to know what to look for.

[@jdillon8360]

@@DrZoidbergism You mean the ECU on top of the pump? That's missing? With or without the timing sensor and the two solenoids? If that's all missing yes you could theoretically use the pump for parts, but all testing and timing has to be done on a Bosch test bench. You can't swap most parts over without losing all the factory settings. Once you pull the timing sensor for example, that's it, it's gotta go on a test bench. You could swap a delivery valve (outlet valve), but you need the right seat washer to go with it. Or the overflow valve. But anything internal means dismantling the pump which means you need a test bench and special tools to set it up right afterwards. No lube usually kills the big roller bearing, the rollers, the cam ring, the internal feed pump and usually causes the timing piston to seize in the housing.

[@valcic1993]

I put caliper for mesure and broke it inside

[@izzietrent8890]

I find diesel fuel in my engine oil is it possible somehow in the pump postnik diesel in my engine oil

[@justinh8059]

Injectors leak fuel into oil

[@TheCaperfish]

biggest pos ever made , bosch should be ashamed of themselves , how do you go from making one of the best pumps ever made p7100 to the biggest pos ever made ???

[@colt098]

I need to replace mine….I should just sack up, spend the money on a ppump conversion huh?

[@hreindustries]

ight now bore it and make vp66

[@cesarjorgemurillobarientos1813]

good

[@TheDieselStop]

Vp44 sucks. P-pump is the boss. Thank you for the video Ed.

[@edzgarage]

True enough! We will be doing more pump teardowns soon and a Ppump is one of them. Thanks for the comment!

[@axemanjoe2945]

They don't suck at all. You just gotta know what you're doing with em. Add a aftermarket lift pump that puts out at least 18psi and get a fuel pressure gauge. I think its ridiculous dodge didn't add one stock.

[@binodbaraili6195]

wOW

[@dancohick6953]

THANKS FOR THE BRAKEDOWN, I wanted to ask if { sea foam, or injector cleaner, or metrical marvel l} could free up the parts when the elec top cap off, let it soak for how long , without taking the pump out ,then put all the top parts back, and see if the pump may operate and pump fuel correctly

[@markvaught8884]

Whats the thread pitch for the bolt you used to pull the fuel solenoid?

[@gasamugove9487]

Great video I urgently need a MAN truck d0836lf3 distributor type electronic version injection pump

[@ramkumar-yh5wo]

When u need..