Injection pump

Drivbiwire

Zehntes Jahr der Veteran
Joined
Oct 13, 1998
Location
Boise, Idaho
TDI
2013 Passat TDI, Newmar Ventana 8.3L ISC 3945, 2016 E250 BT, 2000 Jetta TDI
A question was asked the other day and I replied to it, after rereading it I thought posting it in the 101 section would be a good way to find the post with a forum search for new members under the header of "Injection Pump".

Enjoy!

Repair for Pump case Pressure Regulator: http://pics.tdiclub.com/data/500/VE_Pressure_regulator_Repair.pdf



ALH (TDI) - Manual Pump exploded diagram and parts list: http://pics.tdiclub.com/data/500/Manual_Pump_Parts.pdf

ALH (TDI) - Automatic Pump exploded diagram and parts list: http://pics.tdiclub.com/data/500/Automatic_Injection_pump_038_130_107_J.pdf

AHU/1Z (TDI) - Manual Pump exploded diagram and parts list: http://pics.tdiclub.com/data/500/1Z_TDI_Injection_Pump_Manual_transmission.pdf

AAZ (IDI) - Manual Pump exploded diagram and parts list: http://pics.tdiclub.com/data/500/AAZ_Injection_Pump_Manual_Transmission.pdf

ME (IDI) - Manual Pump exploded diagram and parts list: http://pics.tdiclub.com/data/500/ME_IDI_Injection_Pump_Manual_Transmission.pdf

Information is relevant for the A3/B4 and also the A4 TDI using the VE series injection pump.

PD motors replace this pump with more advanced individual pump injector units.

Inside the TDI injection pump there is a "Cam Plate" that is turned by the pumps timing belt pulley. The cam plate is also turning a small "Plunger", these two assemblies rotate in unison. The rotating plunger is mounted to a stationary plate or "Roller Ring" that has four rollers that provide the contours for the spinning cam plate to follow and cause the plunger to extend in and out on. The cam plate contours are what determines how far the plunger slides in and out of the fuel compression chamber and the size of the contours are what can vary from year to year effectively determining how hight the fuel pressures can reach. Since the roller ring assembly (fig 2) is "mostly" stationary the compression of the small amounts of fuel can occur at exactly the same time. The caviate to this is that the roller ring assembly can be rotated slightly clockwise or counter clockwise effectively adjusting when the compression of the fuel actually occurs without having to integrate a complex system for injection timing.



The looming question is how do you control the quantity of fuel ie speed of the motor? The above describes how you effectively create fuel pressure and adjust timing but the next key is the "Fuel Collar" (Fig 7). The fuel collar is a simple ring that the plunger slides through during each and every injection stroke. In the plunger there is an elongated hole (figure 5, top) that when uncovered allows all remaining fuel in the compression chamber to be vented back into the internal body of the pump effectively ending the fuel delivery for that cylinder. This means that all unused fuel is simply vented internally without having to flow to and from each injector. The injectors ONLY recieve what is needed and the fuel collar is what directly determines engine speed and power output.



So internally you have an oscilating and rotating plunger that aligns with the four or in some cases 5 or even 6 outlet ports depending on the pump layout. In the case of the VW ALH TDI, with every complete horizontal stroke of the plunger, the plunger itself rotates 90 degrees. This means that it goes from start point to full extension and back as it rotates a complete 90 degrees of rotation. With one full 360 degrees of rotation the plunger will actuate 4 complete injection events while varying timing and injection quantity on each and every stroke.



The collar is controlled by an electrical servo that receives its control signal from the cars ECU. The computer looks at all engine sensors and determines when and how much fuel to inject.

On each injector there are fuel return lines. Since the insides of the injectors are not perfect there is sometimes some fuel that is leaked internally. Rather than allowing that fuel to remain in the injector Bosch allows for a return line to return that fuel back to the cars fuel filter where it is recirculated, filtered and eventually burned in the engine.

The pump can be described as having 2 seperate pumps. The first is often described as a "Low Stage Vane type pump" This provides "Head Pressure" to make the fuel push its way into the plunger chamber fast enough not to allow cavitation of the plunger. The pressure of the pump is around around 100 psi. When the plunger compresses the fuel the pressures can reach as high as 19,000 psi at the fuel nozzle.



Hope that helps.

DB
 
Last edited:

gern_blanston

Veteran Member
Joined
Dec 3, 2002
Location
PNW
TDI
Golf, '03, Silver
Cool techno stuff. That's one of the things I love about this car: Useful technology instead of technology for technology's sake, like so many manufacturers purvey.
Ahhhh, to be in the Flight Levels.
 

Drivbiwire

Zehntes Jahr der Veteran
Joined
Oct 13, 1998
Location
Boise, Idaho
TDI
2013 Passat TDI, Newmar Ventana 8.3L ISC 3945, 2016 E250 BT, 2000 Jetta TDI
Salem huh! I am going to be in PDX this weekend and I will have some time to meet up on Saturday. Drop me an email if your interested in meeting up.

DB
 

gdr703

Veteran Member
Joined
Jun 13, 2002
Location
Vancouver, Canada
TDI
Golf 2 door 2002 Indigo
Most interesting, Thank you.
I think I got it.
The fuel pump plunger always travels the same distance, it is the collar that determines when the plunger is pressurising fuel. So on over-run the collar completely uncovers, and the plunger just moves through its cycle without pressurising anything. So the pump is not pressurising fuel unecessarily.
The fuel return line from the injectors is merely for injector leakage, so the flow will be very small.
The timing of the fuel injection on small throttle openings will be slightly advanced when compared to a large throttle demand. Unless this is compensated for by the ECU by adjusting the start of injection cycle.
The other obvious observation is the importance of adequate lubrication in this fine piece of engineering.
once again, thanks for the detail
 

dzljet

Veteran Member
Joined
Jan 6, 2002
Location
TEXAS
TDI
00 Jetta
Pete,
good write up, thanks.

This BTW folks is something we need to see more of that harkens back to "Old Skool" tdiclub and is a welcome site from all the bickering that has gone on entirely too long and degenerated the value of this board.

Huzah, Pete!!!

Perhaps, we could get someone else with time and energy to write up how "tuning boxes" come into play and their pro's and con's.
Just make sure it maintains the same quality.
 

888

Veteran Member
Joined
Aug 1, 2002
Location
SW Ohio 45373
TDI
15 Golf 6MT, 01 NB 5MT shell
FWIW, the whole Bosch VE manual (66 pages) that this came from is available from SAE's website (www.sae.org/ do a search for Bosch VE) in a PDF download for $14.95 US. I actually downloaded it this morning to use on my Dodge Cummins truck, wasn't sure that it was the same pump as the VW. IMHO, for $14.95, you can't beat it. Everything anyone wants to know about the way that the pump works should be in here. I used to write this stuff for a living and I would really recommend it.

Joe
 

gern_blanston

Veteran Member
Joined
Dec 3, 2002
Location
PNW
TDI
Golf, '03, Silver
drivbiwire. Sorry, been in Florida all week. Gotta' fly this weekend, too, or maybe we could hook up. Howw do I contact you via e-mail
 

Growler

Got Soot Vendor
Joined
Nov 24, 2003
Location
Millersport, Ohio
TDI
Schmutz, 2015 Golf Sportwagen DSG & Schnurren, 2001 Golf GL 2 door 5M
WOW, you learn something new every day.

Thank you drivebywire for writing this up for all to learn from.

Aaron
 

Birdman

Top Post Dawg
Joined
Apr 7, 1999
Location
Near Hagerstown MD.
TDI
Jetta 2001 Died by Truck one snowy day. Jetta 2003
[ QUOTE ]
The fuel return line from the injectors is merely for injector leakage, so the flow will be very small.


[/ QUOTE ] Not that small if the hose breaks or more likely rots it will soak the engine very fast. changing return line every 3-4 years is a good idea. When i got my PP205 injectors set up on installing them I must have hit the injector on the end with the rubber boot and a day or so later stopping at a light there was what looked like steam coming from under the hood, the leak was spraying out a pin hole about 2 feet. sure makes a mess.
 

Kiwi_ME

Veteran Member
Joined
Jul 3, 1999
Location
New Zealand
TDI
'18 Kona EV, ex '03 Golf TDI, '82 Rabbit Diesel
So here's a question. I wonder if wear debris from the "Low Stage Vane type pump" would cause eventual damage to the high pressure pump?

I'm not seeing the exact fuel flow path but perhaps there is a small filter in there somewhere.
 

bigpaws1984

Active member
Joined
Jun 30, 2005
Location
arizona
TDI
2002 Golf 5 speed, 2011 Jetta DSG automatic
injection pump top

what could cause the pump to not deliver any fuel after the middle seal was replaced? where does the servo part fit into the bottom of the ip?
 

FlyTDI Guy

Top Post Dawg
Joined
Nov 3, 2001
Location
PNW
TDI
'01 Jetta GLS
Worked fine for me (well after a bazillion pop-ups, cookies, etc.) but... I already had it. I'd re-post it on my server but I need more space. Getting time to upgrade my disc space. It downloads REAL slow... maybe give it more time. Go to store, get dinner, take shower, watch movie, etc.
 

eetsoot

Veteran Member
Joined
Dec 15, 2001
Location
Oxnard, Ca (at least for now!)
TDI
Jetta, 2002, galaxy blue
Sorry about that site. I don't know of many free posting sites. I tried that before I didn't get pop ups.

Anyone know if there is a torque spec for the IP case pressure valve?
 

Real_Diesel

Member
Joined
Dec 27, 2004
TDI
Beetle, 04, Blue
Just found this thread! Great right up! I have a question. I just picked up a 78 rabbit and got it home this morning (it's been sitting for a while) and it just cranked. I broke the injector lines loose, bled it and she fired right up! But, I noticed the Ip is leaking. It appears to be leaking from the back of the pump. It appears to be leaking where the distributor head mounts to the body. From what I've researched, it looks like it's just an o-ring that seals it. Does anybody know if I can remove the 4 bolts from the head, slide the head off, and just replace the o-ring with no plroblems?

Thanks!
 

jimfoo

Veteran Member
Joined
Dec 6, 2007
Location
Evergreen, CO
TDI
1966 Land Rover IDI being converted to TDI
Still need an answer? if so, PM me.
Real_Diesel said:
Just found this thread! Great right up! I have a question. I just picked up a 78 rabbit and got it home this morning (it's been sitting for a while) and it just cranked. I broke the injector lines loose, bled it and she fired right up! But, I noticed the Ip is leaking. It appears to be leaking from the back of the pump. It appears to be leaking where the distributor head mounts to the body. From what I've researched, it looks like it's just an o-ring that seals it. Does anybody know if I can remove the 4 bolts from the head, slide the head off, and just replace the o-ring with no plroblems?

Thanks!
 

Drivbiwire

Zehntes Jahr der Veteran
Joined
Oct 13, 1998
Location
Boise, Idaho
TDI
2013 Passat TDI, Newmar Ventana 8.3L ISC 3945, 2016 E250 BT, 2000 Jetta TDI
Real_Diesel said:
Just found this thread! Great right up! I have a question. I just picked up a 78 rabbit and got it home this morning (it's been sitting for a while) and it just cranked. I broke the injector lines loose, bled it and she fired right up! But, I noticed the Ip is leaking. It appears to be leaking from the back of the pump. It appears to be leaking where the distributor head mounts to the body. From what I've researched, it looks like it's just an o-ring that seals it. Does anybody know if I can remove the 4 bolts from the head, slide the head off, and just replace the o-ring with no plroblems?

Thanks!
It may very well be the plunger head o-ring. Not hard to do BUT you have to be VERY careful when removing the plunger head, if any of the rollers fall out and you mismatch them...overhaul or worse time for a new pump.

DB
 

bdangr

Member
Joined
Jul 24, 2006
Location
Crown Point, IN
TDI
2002 Jetta
VE Injector Pumps and Low Sulfur Fuel

Hello,

I have a 2002 Jetta TDI w/144K and just had the TB changed with a Contech
Kit and a New Water Pump. I went to get the Car and it backfired first and started running. The Garage said, that they had to do some more adjustments. I was told that the timing could not be set at the Factory setting 3 degrees BTC at Idle because something was wrong with it. This was not the result according to them with the installation of the New TB. It was running at
2 degrees - TDC in order for it to run. I finally picked it up and it seemed to run normally 10 miles to my home and I put it in the Garage and then the next day took it out to get it washed and then, back into the garage. I had some problem starting it. Then, it sat in the Garage for about 3 days and I went into start it. All it did was turn over with the Starter and did not reach Compression like it was not getting Fuel.

Now, they have it back again and it is allegedly a Injector Pump internal problem because of Low Sulfur Fuel??????. according to them. I really think I am getting screwed and the price is going up. Could someone out there tell me an expert opinion. Also,
they are telling me a New Fuel Injector Pump is about 3 Grand. I went the VW Dealer in Merrillville, IN and their cost was $1121.06 for 038-130-107JX.
This is with the Core Charge. Can somebody please clarify and tell me what is going on? I would appreciate it very much. My phone number is 312 3750548 and I live in Crown Point, IN.
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
What's going on? Imagine a train. Now imagine a tunnel. Imagine the tunnel is you and the train is the shop. That train keeps going into the tunnel deeper and deeper.

Find a competant shop that isn't trying to screw you.
 

TornadoRed

Top Post Dawg
Joined
Aug 3, 2003
Location
West Des Moines (formerly St Paul)
TDI
2003 Jetta TDI wagon, silver; 2003 Jetta TDI wagon, indigo blue; 2003 Golf GL 5-spd, red (PARTED); 2003 Golf GLS 5-spd, indigo blue (SOLD); 2003 Jetta TDI wagon, Candy White (SOLD)
bdangr said:
I have a 2002 Jetta TDI w/144K and just had the TB changed with a Contech Kit and a New Water Pump.
I'm not familiar with that kit, what parts are in it?

I was told that the timing could not be set at the Factory setting 3 degrees BTC at Idle because something was wrong with it. This was not the result according to them with the installation of the New TB. It was running at 2 degrees - TDC in order for it to run... I had some problem starting it.
Did they use the correct tools to lock the cam and injection pump? Something is not right. Hard starting often indicates retarded timing, but who knows, it sounds like your mechanic has just been guessing all along.

Now, they have it back again and it is allegedly a Injector Pump internal problem because of Low Sulfur Fuel??????. according to them. I really think I am getting screwed and the price is going up. Could someone out there tell me an expert opinion. Also, they are telling me a New Fuel Injector Pump is about 3 Grand. I went the VW Dealer in Merrillville, IN and their cost was $1121.06 for 038-130-107JX. This is with the Core Charge.
More than likely there is nothing wrong with your injection pump. I think it is time to cut your losses and get your car away from that shop before they do even more damage.
 

auto_tech

Vendor
Joined
Jul 13, 2004
Location
Bethany, Ontario
TDI
SOLD - 2001 Jetta blue; 2016 Jetta 1.4TSI 5spd
I wonder if someone could add a write-up of the low pressure side of the pump. Fuel flow through the vanes and pressure regulator. What failures occur and what the effects are as a result. That would also be handy.
 

mirk

New member
Joined
Jun 19, 2008
Location
Athens, OH
TDI
2001 Jetta
WOW, great post! I am complete newb to diesels and tdi's and hope to find lots more info like this on Fred's.

I am currently dealing with what I think to be a failing IP. It is making a LOUD clicking noise at engine startup that seems to stay in time with engine rpms. I am sure it is IP as I have used screwdriver stethoscope and localized noise to IP. I have looked over many many threads trying to determine what is happening here. Could this sound be related to rollers on camplate? I dont see them in any of the diagrams, but assume they are inside the roller ring. If so, does this definitely mean replace the pump?

I have already had the IP timing adjusted by local guru due to hard, smokey starting. This fixed the starting, but this is when I noticed the noise (after learning more about the pump and whatnot). Could have been there since I got it and just thought that was how it was supposed to sound as I have no previous experience.

Oh yeah, this is 2001 jetta, ALH w/ 73k miles. This seems very early for IP failure. I just got the car about a month ago and have put less than 500 miles on it. It came from former club member, has the plate frame and all. I believe the story goes that he passed away and his kid got it and kind of beat it up a bit. (No disrespect intended towards any party) Has lots of service records (dealership) so I thought it was a good buy.

Any help in understanding what my next step should be would be very appreciated. I am hesitant to put another $2k into it and my wife is starting to hound me that I got taken. I am starting to think she is right. Sorry to be long winded and thanks for the help in advance!
 

FlyTDI Guy

Top Post Dawg
Joined
Nov 3, 2001
Location
PNW
TDI
'01 Jetta GLS
mirk said:
WOW, great post! I am complete newb to diesels and tdi's and hope to find lots more info like this on Fred's.

I am currently dealing with what I think to be a failing IP. It is making a LOUD clicking noise at engine startup that seems to stay in time with engine rpms. I am sure it is IP as I have used screwdriver stethoscope and localized noise to IP. I have looked over many many threads trying to determine what is happening here. Could this sound be related to rollers on camplate? I dont see them in any of the diagrams, but assume they are inside the roller ring. If so, does this definitely mean replace the pump?

I have already had the IP timing adjusted by local guru due to hard, smokey starting. This fixed the starting, but this is when I noticed the noise (after learning more about the pump and whatnot). Could have been there since I got it and just thought that was how it was supposed to sound as I have no previous experience.

Oh yeah, this is 2001 jetta, ALH w/ 73k miles. This seems very early for IP failure. I just got the car about a month ago and have put less than 500 miles on it. It came from former club member, has the plate frame and all. I believe the story goes that he passed away and his kid got it and kind of beat it up a bit. (No disrespect intended towards any party) Has lots of service records (dealership) so I thought it was a good buy.

Any help in understanding what my next step should be would be very appreciated. I am hesitant to put another $2k into it and my wife is starting to hound me that I got taken. I am starting to think she is right. Sorry to be long winded and thanks for the help in advance!
Could just be a timing issue. Retarded timing=quieter engine/pump. More advanced timing= louder pump. You should get another opinion on your static and dynamic timing. An expert w/vagcom can look at both and tell you if you're within acceptable tolerances. FYI, a majority of the 'diesel' sound of our engines is the injection pump noise. If you find your pump needs work, contact Diesel Fuel Injection Service (800-547-8454) of Portland, OR and you'll get a much better deal than any dealer or other source.
 
Last edited:
Top