Turbo housing wear?

SteelFace

Member
Joined
Jun 6, 2018
Location
portland
TDI
golf mk4 bew
I have a 2005 mk4 bew TDI with the original turbo and 200k miles. The car started making high pitch sound under light boost and over 2k rpm. I have removed the egr and anti shutter thinking that it may be a vacuum leak on those but that did not help. I have attached pic of turbo. I don't think the shaft play is bad and I don't see score marks but there is discoloration around the impeller. Could the turbo be bad?]

PS. I can't find a way to attach photos :(
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
Go to pics.tdiclub.com, log in again, click upload, follow prompts. As you finish you'll see a place to harvest a link (full size, medium or thumbnail). Paste link back in this thread. Medium or thumbnail displays full size when clicked. Long version in my signature.

Welcome to TDI Club!!
 

flee

Veteran Member
Joined
Sep 19, 2011
Location
Chatsworth, CA
TDI
2002 Jetta GLS wagon
I had to replace mine at around the same mileage. No increase in oil consumption.
I drove it for a few months while shopping for a replacement turbo but YMMV.
 

SteelFace

Member
Joined
Jun 6, 2018
Location
portland
TDI
golf mk4 bew
Thanks for the replies. I was able to pinch off the vacuum line going to the turbo actuator and that seamed to do the trick in making the noise go away. I drove carefully as I am not sure what the vacuum signal does. Does the vacuum tell the turbo to start building boost, or is the vacuum signal used to tell the turbo that the boost is at target levels and to stop creating more boost?
 

flee

Veteran Member
Joined
Sep 19, 2011
Location
Chatsworth, CA
TDI
2002 Jetta GLS wagon
The vacuum moves the actuator which increases boost.
Just make sure there's no boost leak - your 'test' doesn't narrow down the source of the noise.
If the discoloration ring is nearest the impeller blades that is a pretty good sign of contact, though.
 
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BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
..................... I was able to pinch off the vacuum line going to the turbo actuator and that seamed to do the trick in making the noise go away................
That's gotta be a clue. The turbo will continue to spin with the hose pinched.
Someone correct me if I'm wrong, but wouldn't that leave it at full boost?
 

SteelFace

Member
Joined
Jun 6, 2018
Location
portland
TDI
golf mk4 bew
There are Couple things to note.

I went to a local shop to discuss the possibility of my turbo going bad. The shop had a Subaru turbo he was just replacing and showed me what a bad turbo looks like. There was score marks where the impeller had interfered with the turbo housing, and there was a lot more shaft play than what my turbo has. You were also able to turn the impeller by hand and have it squeak as the impeller caught the housing. I do not have any of these symptoms. There is discoloration of the turbine housing around the impeller, but I have not found an image of a turbo that didn't have this....

So no vacuum signal to the turbo means that the turbo will not build up boost? This is good to know.
 

SteelFace

Member
Joined
Jun 6, 2018
Location
portland
TDI
golf mk4 bew
The vacuum moves the actuator which increases boost.
Just make sure there's no boost leak - your 'test' doesn't narrow down the source of the noise.
If the discoloration ring is nearest the impeller blades that is a pretty good sign of contact, though.
I feel that my test does indicate that the noise is somehow turbo related. Possibly a vacuum leak and air being pulled through a small orifice that is causing the squeeling whistling noise? Maybe my actuator diaphragm is busted and I'm pulling air through it? Maybe too much shaft play in the turbo?
 

SteelFace

Member
Joined
Jun 6, 2018
Location
portland
TDI
golf mk4 bew
Here is my next move.

1) I am going to get a boost gauge to see what my current boost levels are.
2) Do a boost leak test on the car
3) Hook up a vacuum gauge to the turbo actuator and see what I am getting. What type of vacuum should I expect when running the car?
4) Make sure that the turbo actuator is not stuck
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
The only thing the vacuum does is operate the actuator which moves a lever that opens and closes the vanes. The 2005 has wires connected to it, I have no idea how those come into play.
Your possible vacuum leak is accurate. Connect a vacuum pump and gauge directly to the actuator, pump it up to 10"/Hg or so and see if it holds.
 

SteelFace

Member
Joined
Jun 6, 2018
Location
portland
TDI
golf mk4 bew
The only thing the vacuum does is operate the actuator which moves a lever that opens and closes the vanes. The 2005 has wires connected to it, I have no idea how those come into play.
Your possible vacuum leak is accurate. Connect a vacuum pump and gauge directly to the actuator, pump it up to 10"/Hg or so and see if it holds.
I hooked up a vacuum pump on my lunch break and I can hold steady vacuum of 10"/Hg all day long on the turbo actuator. Once I get home I will crawl under the car and see if the vacuum is actually moving the turbo actuator arm.

I also think that when I pinched the vacuum hose it threw my car into a limp mode since I did not have any noise on my way to work, and uphill climbing is a chore. I will hook up a diagnostics tool and clear the limp mode when I get home.

Does anyone know what allows the vacuum to be sent to the turbo actuator? Is there a manifold that could be faulty upstream from where I was pulling the vacuum onto the turbo actuator. Maybe there is an air leak there?
 

KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
10" With the pump running sounds like a leaker.
Or did you pull it down, shut off the pump and it held 10" with the pump off?
 

SteelFace

Member
Joined
Jun 6, 2018
Location
portland
TDI
golf mk4 bew
10" With the pump running sounds like a leaker.
Or did you pull it down, shut off the pump and it held 10" with the pump off?
I disconnected the vacuum hose that goes somewhere in the car (I have not traced where it goes) and plugged a hand held vacuum pump to the nipple on the turbo actuator. The actuator does hold pressure at 10" vacuum.

What type of vacuum would you expect the car to be sending the actuator?
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
I believe the range at the actuator is 3.5 to 18, approximate.

The book adjust for the ALH is to just start moving at 3.5 to 5.0 "/Hg. I believe it's the same for PD.
 

KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
The running pump is capable of well over 20 inches but it is modulated by the N75.

If yours holds 10" locked up I'd call it good.
 

SteelFace

Member
Joined
Jun 6, 2018
Location
portland
TDI
golf mk4 bew
OK so I did some further digging now that I got home from work. The actuator starts to move at about 4" vacuum so I do not think that my vanes are sticky.

I then proceeded to T off into the vacuum line going to the turbo. while driving and flooring the gas the vacuum going to the turbo actuator would jump up to 20-25" vacuum but the car didn't feel like I was getting any boost. My obd reader was giving me a signal of calculated boost of 1.1 psi, but I'm not sure if that is correct.

I am getting a boost gauge tomorrow to see if I truly have 0 boost. Now im off to get equipment for a boost leak test.

To me it seams that unless I have a huge boost leak, the turbo is toast. Interesting thing is that now I am not getting any noise from the turbo. Maybe it just stopped spooling up?
 
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wonneber

Top Post Dawg
Joined
Oct 12, 2011
Location
Monroe, NY, USA
TDI
2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
Maybe I missed some of this.
Your actuator starts to move at 4 inches which is good.

Did you continue to 17 inches (or so) which should be maximum travel on the arm going into the turbo.
It should also move smoothly.

Another test would be taking the actuator off the arm (1 e-clip) and move the arm full travel to check for smooth operation.
Don't know about BEW but it's only 2 more nuts to remove my actuator.
Also check for rust inside the actuator. VW Bulletin about this.

If it's not smooth I've read others worked it full travel for 5 minutes (or so) to clean up the carbon buildup.
Tie a piece of thread or floss to the e-clip for when you re-install it. It's easier to find it when it slips & flies.
 

SteelFace

Member
Joined
Jun 6, 2018
Location
portland
TDI
golf mk4 bew
Maybe I missed some of this.
Your actuator starts to move at 4 inches which is good.

Did you continue to 17 inches (or so) which should be maximum travel on the arm going into the turbo.
It should also move smoothly.

Another test would be taking the actuator off the arm (1 e-clip) and move the arm full travel to check for smooth operation.
Don't know about BEW but it's only 2 more nuts to remove my actuator.
Also check for rust inside the actuator. VW Bulletin about this.

If it's not smooth I've read others worked it full travel for 5 minutes (or so) to clean up the carbon buildup.
Tie a piece of thread or floss to the e-clip for when you re-install it. It's easier to find it when it slips & flies.
Thank you, Yes it fully extends at around that much vacuum. I have yet to try to work the lever but that will be next. I couldn't find a valve to do a boost leak test so I had to order that. I also ordered a seal kit for all of pressure side components from ID parts.

Maybe my actuator arm is broken and the vanes are not moving inside the turbo? I will be taking the car apart this weekend to investigate.
 

wonneber

Top Post Dawg
Joined
Oct 12, 2011
Location
Monroe, NY, USA
TDI
2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
Maybe my actuator arm is broken and the vanes are not moving inside the turbo? I will be taking the car apart this weekend to investigate.
I have read about that once or twice that I remember.

I found a boost leak spraying soapy water on the boost tubes with the car running at idle.
Tiny crack near when the tube rubbed a pulley.
 

snakeye

Veteran Member
Joined
Dec 13, 2009
Location
Montreal, Canada
TDI
2003 Jetta and Wagon, GLS 5sp
What about an exhaust leak? The turbo sound is more noticeable if you have say a leaky downpipe. What kind of noise are you hearing exactly? Is it clearly the turbo spooling? I once had a chirping sound that I thought was the turbo. Turns out my intake manifold was loose.
 
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