VNT Repair Procedure

[Drivbiwire]

If you have a turbo that is jammed up and causing an Overboost code, you will need to follow the following procedure. To keep the file size to a minimum, I eliminated the removal process and kept it to strictly the repair of the turbo.

This issue is often caused by "Babying" the motor and short shifting at low rpms. People who have this issue are often the ones that have been being gentle with the motor and not following my guidelines of shifting at 2500rpm when cold and at no less than 3,000 rpm when warm.

Anyway, here is what you need to do to fix your turbo:

http://pics.tdiclub.com/data/500/Drivbiwire_VNT_repair_procedure_small.pdf

And when it is all said and done this is how your VNT actuator rod will move!

http://pics.tdiclub.com/data/500/2006_0603_175432AB.AVI

DB

 

[edfcmc]

Awesome

Awesome Drivebywire. They should make this a sticky.

Note: Nuclear Grade AntiSieze is available from McMaster-Carr.

Search for item 1027K33.

 

[wanders]

Outstanding! Thanks!

 

[richieracket]

dbw--excellant post--you're dedication to this site and tireless work with such explicit posting is truly appreciated and invaluable to me and i'm sure many others here.

 

[cage]

Looking at the intricacies and conditions the VNT has to deal with I'm surprised they work at all! Talk about a hostile environment. I can't even keep my Beetles door hinges lubed adequately!
Great post!

 

[whitedog]

Nice pictures and well done. Question: Would bead-blasting the outer housing be OK, taking proper care that the area where the vanes run are protected? I had shivers just thinking of that pick scraping that rust.

 

[Drivbiwire]

Regarding bead blasting. I would use a very specific blasting media: Walnut Shells but NOTHING ELSE.

When the turbo is apart you can see all the contact areas (lots of them) these have nicely machined smooth surfaces, I would not want to damage them with abrasive media like glass beads or worse yet sand.

Emery cloth works well, just don't expect to have newly machined surface appearance. All that matters is getting the rust and soot out of the VNT mechanisms followed by a lecture on how to drive the TDI to prevent this from happening in the first place

Total time for this job: 1.5 hours to pull the turbo, 2 hours to clean the turbo, 1.5 hours to re-install the turbo.

No adjustments are needed to the VNT nor should you make ANY attempt at messing with the factory settings!

DB

 

[jasonTDI]

I've been doing a LOT of these lately. Sometime the issue is you can't get the turbo APART to clean it, they actually rust together in some situations. Soaking for 2-3 days won't get them apart, all you can do is work the actuator a LOT and hope you break it free.

 

[compu_85]

Well, mine is getting stuck again, in the same spot it was getting stuck before I freed it.

Should I look into pulling the turbo and doin this? Someone suggested retarding the timeing in vag-com and then doin some WOT runs, but this sounds very dangerous

-Jason

 

[pghPAtdi]

I go through this cycle too. Works like new, full smooth travel. Then one day it's getting stuck again in the same spot. Then back to being smooth
BAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

Well, mine is getting stuck again, in the same spot it was getting stuck before I freed it.

Should I look into pulling the turbo and doin this? Someone suggested retarding the timeing in vag-com and then doin some WOT runs, but this sounds very dangerous

-Jason

 

[Drivbiwire]

It's rust or corrosion in the VNT ring perimeter that is binding things up. Despite loosening it up there is nowhere for the stuff to go and remains in the ring area.

Look at one of the first pictures and you can see all the debris that accumulates on turbos that develope this issue.

DB

 

[whitedog]

It's rust or corrosion in the VNT ring perimeter that is binding things up. Despite loosening it up there is nowhere for the stuff to go and remains in the ring area.

Look at one of the first pictures and you can see all the debris that accumulates on turbos that develope this issue.

DB

With a good look at the turbo cleaning pictures (thanks) it is obvious why squirting your favorite lubricant on the shaft will not have any effect on this rust. It's just too far in past too much stuff. If it frees up with some lube, that means it wasn't rust around the ring and/or it vill be bach.

 

[pghPAtdi]

 

[DeafBug]

Great write up! You should put some sentence in there. Some of the pictures I had no idea what the intention is.

 

[Drivbiwire]

I can tweak it and add more information. Let me know if you have any suggestions.

DB

 

[Diesel Drvr]

Yes, it is an excellent document but it would be nice to have a brief explanation for non-technical people like me. Dealer told me my turbo is gone and it is the vnt that is stuck. They are trying to get it covered under my recently expired warranty since my extended warranty will not cover it.

You made a comment in your post about driving it the right way. Could please fill me in.

 

[apari006]

try googling this (only the pdf file seems to work):Intake manifold cleaning 101

also check this out: http://forums.tdiclub.com/showthread.php?p=502340

A

 

[Gringo]

Drivbiwire, great write-up.
Just a few question on how to actually remove the turbo. I removed an intake manifold before for cleaning purposes with no problems, but this was done without removing the coolant hoses going to the EGR cooler. CAN THE HOLE ASSEMBLY BE REMOVED AT ONCE (EGR, EGR cooler, intake manifold, exhaust manifold and turbo) or do we need to take averything apart piece by piece?

Here are the steps I can understand to get the turbo on the work bench.

1. remove the rubber intercooler hose.

2. remove EGR return pipe #1 (4x 6mm hallen)

3. remove EGR return pipe #2 (2x 8mm hallen and 2x 11mm ex-head).

4. remove EGR coolant hoses (2 rubber hoses).

5. remove EGR cooler (3x 10mm ex-head)

6. remove intake manifold (8x 8mm hallen).


(this is where know territory ends)


7. remove oil line to turbo (rubber or steal ???).

8. remove banjo bold (other pipe coming from turbo, what is it for?)

9. remove exhaust manifold (8x ex-head or hallen ???)

10. un-bolt turbo bracket (one bolt)



I know, I should find myself a bantley manual....

How accessable is all this? I assume that some of the bolts can only be accessed from under the car?

Sorry for the multiple questions,

 

[Drivbiwire]

The easiest way to pull the turbo is piece by piece.

If you pull just the turbo there is no need to disconnect the cooling lines to the EGR cooler.

DB

 

[Bob_Fout]

Yes, it is an excellent document but it would be nice to have a brief explanation for non-technical people like me. Dealer told me my turbo is gone and it is the vnt that is stuck. They are trying to get it covered under my recently expired warranty since my extended warranty will not cover it.

You made a comment in your post about driving it the right way. Could please fill me in.

http://forums.tdiclub.com/showthread.php?t=48940

 

[Drivbiwire]

DB

 

[Burl4561]

Awesome PDF once I finally got it to load.
I very much hope I don't have to do this to solve my slow boost issue.

 

[jasonTDI]

The easiest way to pull the turbo is piece by piece.

If you pull just the turbo there is no need to disconnect the cooling lines to the EGR cooler.

DB

IF you can get some of those rusted mothers apart......

 

[pghPAtdi]

IF you can get some of those rusted mothers apart......

Mother... what?.....

 

[Bob_Fout]

Mother bolt?

 

[TIDITDI]

any turbo rebuild shops out there?

Dealer is "estimating" $1,800 to replace my turbo - so it will be more than that. (got 182,000 Km on it).
Your instructions and photos on removal and cleaning are great - but I am not sure I am capable of that - Are there any shops in SW Ontario that rebuild these things if I can get it off? A local scrap dealer wants $750 for one with the manifold - and of course no guarantee it is any better than mine of course. Actuator lever only moves half way.

 

[PDJetta]

I thought you could buy them new at IMPEX for less than $1000.

--Nate

 

[katipo]

Mother... what?.....

Mother of ALL bolts

 

[jasonTDI]

Alos, something to consider here is if after cleaning the actuator vacuum pot still does not move freely you need to replace that. After cleaning a turbo today and still having an actuator that worked like c***, I replaced it and the can made 18lbs if boost NOW! It made 4 before. Left a 40 foot soot trail on the road in first and second gear as the owner left today.

 

[Fortuna Wolf]

I have a tool request....
I have attempted to use open ended crows foot wrenches, and the other end which is star shaped. Both of these slip on the heavily rusted bolts on a turbo tht I'm working on.
What should I use to get particularly stubborn bolts out? I would use a socket but I can't fit my socket and racheting wrench in there.