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Vnt Tdi Turbo: How To Adjust Actuator & Cure Boost Problems



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#391 Mangoart

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Posted 23 September 2014 - 12:33 PM

Hi,

 

I have uploaded a new graph with more info on it. I hope it helps.

 

Just to confirm the turbo was brand new and supplied to me by turbo developments and bolted straight on to the car.

 

Thanks Toniattachicon.gifRun Graph 2.jpg

Has anyone had a look at the graph or in the position to offer some advice ?




#392 vrus13

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Posted 30 September 2014 - 12:41 PM

Hi all!
I have a little problem with my car.Passat 2003,avb.
My turbo is a recon turbo. I had boost problem.I think the boost is already good. But, my mileage is very poor. Maybe my actuator is misadjusted. The default setting is:  it starts to move 3-5inhg and stops at 18-20inhg. The another setting is: duty cycle is 70-80% at 4000rpm. If i set the actuator according to 4000rpm,my rod stops at 14-15inhg. If is set the rod lenght and it stops at 18-19inhg,then my duty cycle is ~60%. What is wrong?


#393 Mangoart

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Posted 09 November 2014 - 03:39 PM

Has anyone had a look at the graph or in the position to offer some advice ?

Can any one help... ???



#394 r4vvm

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Posted 26 November 2014 - 04:41 PM

ScreenShot2014-11-23at211249_zps27dce1e7

 

 

Any chance anyone in the know could take a look at this graph please and give me their opinions? 



#395 golfgttdi115

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Posted 23 December 2014 - 10:29 PM

Hi fenwick458 just been reading all your info regarding the vnt turbo ive got a couple of questions i need help with as much info would be very appreciated.

 

Q1. Ive currently got a mk4 golf gt-tdi 115 on a W reg what upgrades could i possibly do to it to make it boost harder and go faster.

 

Q2. Ive bought a boost gauge for my golf and its boosting at 1.5 - 2.0 bar or psi never understood psi or bar lol ive also chopped my back box off NOT the cat as of yet although ive heard several people have done away with the cat for better performance ive added a manual boost controller aswell and a RAM AIR induction kit. 

 

My main questions are what turbo upgrade can i put on my car, what injectors, fmic, and what map could i go for i had a mk4 golf previously that was 198.8 bhp NON PD ENGINE what had a remap, egr delete, bigger injectors, fmic hybrid turbo. 

 

if you could advise me in the right direction i would appreciate it many thanks as you can see iam a newbie in here so please bare with me :) 



#396 Mangoart

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Posted 09 February 2015 - 08:52 AM

Has anyone had a look at the graph or in the position to offer some advice ?



#397 Mangoart

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Posted 09 February 2015 - 08:53 AM

Anyone please !!!!!

#398 Aleksandar Cenov

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Posted 14 August 2015 - 01:19 PM

 
 

hello my car is mk4 AHF 1.9 I have boost meter and I have noticed 1.8 bar when i press full throttle

so I have lengthened the actuator and made this log

What do you think is it possible to be n75?

The turbo is bv39 Borgwarner.

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  • Attached File  log.JPG   58.26KB   8 downloads


#399 madman

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Posted 14 August 2015 - 04:28 PM

Make sure you dont have any vacuum leaks on the pipework.



#400 Aleksandar Cenov

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Posted 16 August 2015 - 02:57 PM

today I have checked n75  it has 18 ohm, and make 0.5 bar (14.74 inhg) car idling 

tandem pump(lukas) make 0.9 bar (26.6 inhg) - the connection to servo is loose 

when i start the engine the actuator didn't move 

 

edit: 

I have changed actuator, now the boost control is better, may be I need more lenght ...

Attached File  log1.JPG   73.33KB   2 downloads


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#401 tdimiketdi

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Posted 12 September 2015 - 07:00 PM

Can anyone help me with mine? Car had turbo replaced by main dealer just before I purchased it but something isn't right with how its set up. I've been told I need to lengthen the actuator to try and help it, but my duty cycle is getting really low at high rpm.... Car is a 2.0 tdi with BKD engine

 

 

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  • Attached File  run1.png   146.64KB   14 downloads


#402 Dan FR

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Posted 13 September 2015 - 07:31 AM

Mk5 platform runs in the opposite direction . Really low DC means it's trying to reduce boost as much as possible. Certainly looks like a longer rod will help

gallery_39141_35970_27324.jpg

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#403 tdimiketdi

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Posted 13 September 2015 - 10:27 AM

Mk5 platform runs in the opposite direction . Really low DC means it's trying to reduce boost as much as possible. Certainly looks like a longer rod will help

Thanks Dan. I'm aiming for 30% at 4000 RPM if I've been reading right? Will a longer rod reduce the lag?



#404 adamp91

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Posted 15 September 2015 - 04:45 PM

Been having boost problems for nearly 6 months now. mk iv golf with charge pressure control, negative boost deviation.

 

so I read online about it possibly being the vnt vanes stuck which was right as they they were completely jammed. Sorted that problem out by removing it and giving it a good clean. the rod now moves and responds to vacuume.

 

My vac pipes were tatty and old so replaced all of those, cleaned the egr valve assembly and intake manifold.

 

I still have issues, nothing has changed!

 

I have logged block 03 and block 11, will come back with a better log soon as it takes me a long time to get to 4000rpm at the moment and I ran out of road.

 

Attached File  block3.png   123.21KB   11 downloadsAttached File  block11.png   154.96KB   10 downloads

 

 

Group B:    '011            
    Engine speed            Spec. intake press.            Actual intake press.    D.cycle MAP
TIME    2850-3150                2000-2150                    2000-2200            40-95%
STAMP     /min                        mbar                     mbar                    %
48.55    1176                        1009.8                    999.6                    20.7
49.38    1176                        1152.6                    1009.8                    21.5
50.2    1155                        1142.4                    999.6                    21.1
51.01    1176                        1152.6                    1009.8                    20.7
51.81    1155                        1152.6                    1020                     20.3
52.61    1155                        1152.6                    1020                    20.3
53.41    1155                        1203.6                    1030.2                    20.3
54.21    1176                        1193.4                    1030.2                    21.5
55.01    1176                        1162.8                    1030.2                    21.5
55.81    1176                        1264.8                    1030.2                    22.3
56.66    1239                        1672.8                    1081.2                    26.7
57.48    1365                        1815.6                    1142.4                    21.1
58.29    1449                        1897.2                    1213.8                    23.1
59.09    1575                        1999.2                    1305.6                    24.7
59.89    1785                        2091                    1662.6                    41.4
60.69    1974                        2091                    1999.2                    55.8
61.49    2163                        2091                    2060.4                    57
62.29    2310                        2091                    2091                    59.4
63.08    2541                        2091                    2040                    58.6
63.89    2688                        2091                    2029.8                    56.6
64.69    2898                        2091                    1989                    54.2
65.49    2919                        2091                    1968.6                    50.6
66.28    3045                        2091                    1989                    48.2
67.08    3171                        2091                    2040                    49.4
67.88    3255                        2091                    2111.4                    51
68.71    3381                        2091                    2111.4                    51.8
69.54    3213                        1203.6                    1632                    39.8
70.35    2163                        1152.6                    1183.2                    39.8

 

 

 

Group A:    '003            
    Engine speed            MAF (specified)            MAF (actual)    EGR duty cycle
TIME    820-900            230-420                            230-420            10-95%
STAMP     /min             mg/R                             mg/R                 %
48.97    1197            365                                583.1                80.9
49.78    1155            250                                480.2                84.5
50.61    1155            415                                465.5                76.9
51.41    1155            415                                656.6                84.5
52.21    1155            425                                573.3                84.1
53.01    1155            490                                573.3                84.5
53.81    1155            475                                504.7                79.3
54.63    1176            445                                676.2                84.5
55.41    1176            490                                646.8                84.5
56.25    1197            850                                588                    4.8
57.06    1323            850                                519.4                4.8
57.89    1407            850                                686                    4.8
58.69    1512            850                                808.5                4.8
59.49    1680            850                                857.5                4.8
60.29    1932            850                                1141.7                4.8
61.09    2079            850                                1190.7                4.8
61.89    2247            850                                1239.7                4.8
62.69    2478            850                                1024.1                4.8
63.49    2583            850                                1097.6                4.8
64.29    2793            850                                1009.4                4.8
65.09    2940            850                                1014.3                4.8
65.88    3024            850                                1004.5                4.8
66.68    3129            850                                970.2                4.8
67.48    3213            850                                945.7                4.8
68.28    3276            850                                1058.4                4.8
69.12    3402            850                                1024.1                4.8
69.94    2352            240                                700.7                4.8
70.75    2079            240                                455.7                4.8

 

 

another set of logs.....

 

If anyone can shed any light on where I should be looking that would be great. Tonight I have swapped my n75 with a known working one which hasnt resolved the problem. I am running out of things to check....

 

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#405 johnnyroper

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Posted 05 April 2016 - 10:29 AM

first post so hi all stumbled on this excellent thread after googling about my boost issue.

sorry to resurrect an old thread but after some advice on a boost issue.

not a golf but a 2002 galaxy with AUY 115bhp engine,i have had it about 8 months and it has been ok but recently does not really boost until 1850rpm but will also overboost and go in to limp when pushed towards 4k rpm.
it had a recon turbo about 18 months ago so I think the settings are the issue.
I have run block 11 test and rpm went up to 1400 and vnt actuator operates.

done a test run flat out in 3rd and duty went up to 94% at 3600 and went in to limp.

I have tried to log in excel as a graph but cannot get it right so it shows the details correctly.

from what I have described can any of you clued up people advise if an incorrectly adjusted rod would cause lag and over boost or am I looking at something different?

cheers
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#406 suhailkhan

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Posted 18 May 2016 - 04:48 PM

Hi johnny
My car actuator arm have been lengthening for past weeks..bit at a time. If the car has a short arm,it will definitely not be laggy,it will have boost on tap and just spikes Upto 3400ish rpm..if you keep on accelerating Upto 4.5k revs the car will go into limp mode
I have lengthened mine nearly 8threads because it was a recon and I was getting 94.4% duty cycle ..now it's reduced quite a lot on full load..however Upto 1900 revs it feels laggy now but very strong from 2-4.5k rpm
Hope that helps

#407 suhailkhan

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Posted 18 May 2016 - 04:50 PM

Just a quick question for the pros out there

When lengthening my actuator,the spool noise has changed alot and it alot more whistly especially when changing gear as I come off boost...the whistle is longer and higher pitched.is this normal?
Thanks in advance

#408 madman

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Posted 20 May 2016 - 06:59 PM

Probably the blades hitting the fan!! Dont worry it wont last long till it wears away and you can just replace the turbo.



#409 Kaos85

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Posted 03 September 2016 - 12:19 PM

hi guys iam new here but been following the forum for some years been helpful thanks.

i have a 2006 a3 pd140 dsg and been having boost issues after it was mapped. its spiking to atleast 29 psi / 2 bar  as it changes into 3rd and 4th. ive used vcds lite to try log this and made the graph, could someone please try interpret it for me. thanks in advance

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#410 gerrywac

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Posted 03 September 2016 - 01:25 PM

Just a quick question for the pros out there

When lengthening my actuator,the spool noise has changed alot and it alot more whistly especially when changing gear as I come off boost...the whistle is longer and higher pitched.is this normal?
Thanks in advance

If you are one of those that has the whistle (not everyone does but they're not uncommon and don't necessarily indicate a problem) then adjusting the rod length affects the spool speed of the turbine and the pitch of the whistle.

I note someone replied suggesting the noise is due to the vanes hitting the turbine and you will wreck it.

AFAIK there are internal stops in the turbo that limit the movement of the vanes so there is no way they can either close completely out come into contact with the turbine through over-adjusting the actuator push rod.

I've had my mk5 over 5 years and it whistles now the same as when i got it over 40k miles ago

seems like it's getting more and more common this, so i've decided to write a little guide about it as i am particularly bored right now.......[O]
firstly, if you have any sort of problems then step 1 is always the same, diagnostics.
Step 1: using VAG COM log block 11 from 2000rpm to 4000rpm in 3rd gear on a flat straight bit of road
from this info in the log file, I can tell you everything about what the engine/turbo/ECU is doing. It means you can start diagnosing and faultfinding, it's no good posting up on the forum "help, my cars in limp mode when i floor it uphill, WTF do i do?" and then when somebody replies "probably the MAF mate" so then you go out and spend £80 odd quid on a new MAF (or however much thesy cost nowadays) and fit it on the off chance that it might fix the problem........
when you log block 11, you will end up with a whole bunch of numbers that look like this.

Group A:'003Group B:'011Group C:Engine speedMAF (specified)MAF (actual)EGR duty cycleEngine speedSpec. intake press.Actual intake press.D.cycle MAPTIME790-870230-310210-35040-75%TIME2850-31502200-24002100-260035-80%TIMEMarkerSTAMPRPM mg/str mg/str %STAMP /min mbarmbar %STAMP0.421428501068.24.80.0120582325.62316.661.81.222898501053.54.80.822052335.82328.363.82.0324158501048.64.81.62235223462351.764.92.8625628501058.44.82.45247823462351.764.93.6826888501058.44.83.28262523462375.167.34.48281485010294.84.08275123462375.167.35.2829198501014.34.84.88287723462351.768.16.0830458501004.54.85.6629822346234067.36.883129850999.64.86.4830872346234067.37.683213850975.14.87.28317123462351.768.58.4832978509804.88.08325523462328.367.79.283381850970.24.88.88333923462351.768.510.063444850970.24.89.68342323462363.469.710.883507850955.54.810.46348623462351.770.111.683591850940.84.811.28354923462351.770.112.483654850935.94.812.0836122346234069.713.2837178509314.812.88367523462363.470.914.093780850945.74.813.68373823462375.172.114.923843850940.84.814.51380123462386.874.1
which aren't much use like that, it makes it much clearer and easier to read if you convert it into a graph and then post the graph up. (btw....the above is not a really bad example, i have seen much worse attempts. some of which are just rows and rows of numbers with no headings![^o)] ) to make it clear and increse your chance of someone helping you you should make a graph and post that up, to make a graph heres what you need to do:


a graph of block 11 will look like this
pd130graph-1.jpg
What do all the numbers mean??
RPM is obviously the engine speed,
Requested boost is how much boost the turbo should be making according to the map like in the ECU
Actual boost is how much boost the turbo is making, measured by the MAP (Manifold Absolute Pressure) sensor. this should abviously be similar to the requested value, however it's normal for it to have a little bit of lag, and then spike as the turbo spools up before returning to "about the same as the requested value"
N75 Duty Cycle this is given as a %, the highest it reads to is 94% and the lowest is around 30% but don't quote me on that. A low duty cycle equates to the ECU asking for more boost from the turbo, and a high duty cycle means the ECU has too much boost already and is requesting the boost be lower. so looking at the graph as accellerator is pressed, more fuel is injected and more boost is requested, as the boost is requested you will see the duty cycle go down, the boost will then rise to the required value as the turbo spools up and then the duty cycle will increase as you go up the revs. it does this because the amount of air flowing through the turbo is increasing, and with that increasing the need for the the vanes to close and build more boost is decreasing, hence the duty cycle rising.
*Note, for both of the boost readings they are in mBar and Absolute. Absolute means it's including atmospheric pressure which is normally around 1 Bar give or take a few millibars. so to get into a figure we work with (Bars of boost) you need to divide by 1000 and then subtract 1 Bar (If you happen to live at a great height from sea level then you should take this into account as the atmospheric pressure will be different)
** Another note, the figures you see in VAG COM also may not be all there is too it, because of limiters it will only show upto 2983.5 mBar, this is the limit of what VAG COM can read from a standard ECU. even if you were to fit and calibrate in a 4 bar MAP the actual boost would still never read above this even though the ECU is capable of measuring above it, it still doesn't let VAG COM show the real amount. the requested boost will also only show upto 2601 mBar for the same reason, and the only way to get around it is to edit the conversion factors in the ECU which sadly no tuners that I know of in the UK are able to do. I don't know how to do it, and this is all the other info I have about it if you are curious:


How the N75, Vacuum system, Actuator and VNT turbo work.
How a VNT turbo works
by using some adjustable vanes inside the turbine housing, it's possible to increase flow over the turbine wheel and speed it up at lower revs, this means it can spool up quicker than the traditional wastegate turbo. then once the engine speed is fast enough the vanes open up as there is now enough air moving through the turbo to spin the turbine fast enough without the need for the vanes to be closed
this video shows the vanes in action:

N75
N75.jpg
it is basically a simple Y valve inside, the vacuum comes in at the top "vac in" and then depending on the duty cycle from the ECU it will either

  • send all of the vacuum out of the "vac out" line to the actuator (low duty cycle, more boost requested)
  • send all of the vac out to "atmosphere" (high duty cycle, less boost requested)
  • or anywhere inbetween
Actuator
turbo.jpg
the actuator controls the VNT rod, which controls the VNT mechanism (the vanes) which ultimately determine the boost the turbo produces. it's moved one way by vacuum, and in the absence of any vacuum a spring will return it to it's resting position.
The Vacuum system
on your TDI you might get confused faultfinding with the multitude of vacuum hoses you will see scattered around the bay. this is a simplified version of the vacuum system, it's exactly how it is on my car so if you have deleted your EGR and you are looking for a vacuum leak, it make sense to just rip everything out and pipe it like this, it will make it easier when you are faultfinding.
vacsystemsimplification.jpg
Common problems
probably the most common is sticking vanes, also you could have incorrect VNT rod length, incorrectly setup stop screw or a vacuum leak/blockage.
if the vanes are stcking then they are just going to jam in any position, normally fully closed, and then once the N75 cannot control the amount of boost (i.e if actual boost is not near enough to requested boost for a given amount of time) then it will go into limp mode
if there is a vacuum leak then there might not be sufficient vacuum in the line to pull the actuator down acainst the spring, move the VNT rod , close the vanes and generate boost, if this happens then after a certain amount of time (~2-3 sec) and still not enough actual boost then it will go into limp mode
if the VNT rod is too short then it will effectively make the turbo far too sensitive and as soon as the ECU requests boost, before you know it you have twice the amount of boost requested as it suddenly spikes. once it does this, it's basically lost control of the boost and for some reason it won't go into limp mode, instead you will just feel a flat spot and if you have a boost gauge you will notice it going off the scale! the reason for the flat spot is the amount of EMP (exhaust manifold pressure) suddenly generated is too much to get though the turbine, so the engine is choked and held back. once the boost falls to a reasonable level you will feel the car start to pull again.
if the VNT rod is too long it will mean the turbo is not responsive enough and it may feel sluggish and laggy.
Vacuum leak, if you have a vacuum leak then it will be the same as above, sluggish and laggy as the N75 will not be able to apply enough vacuum to the actuator
Vacuum Blockage. one example of this is if the atmosphere line from the N75 is blocked then then it will have no way to vent the vacuum away from the actuator, and it will simply send 100% vacuum to the actuator at all times which will most probably end up in limp mode as the vanes will be jammed shut.
Checks and Procedures
How to check the Vacuum system
The most basic way to do this is remove the middle hose from the N75 and suck on it, you should be able to build up enough vacuum to move the VNT lever all the way to the stop screw. once there if you hod it for 1 minute and the lever does not move then all is working as it should be. if the VNT lever starts returning straight away, then theres a leak either in the vac pipe or the actuator diaphragm. if you have a vacuum pump you can use that to do this check, the vacuum will fall slightly on the gauge but as long as it's not rapidly descending it it ok.
http://cgi.ebay.co.u...em=230477698201
How to check the N75
perform an N75 output test using VAG COM and you should be able to see the actuator moving and hear the exhaust tone changing. alternatively you could swap the N75 for a working one to see if that changes the problem before buying a new one. N75's are very reliable, most of the time its something else causing the problem. also, if you remove the MAP sensor plug temporarily with the engine idling, you should hear a noticeble change in the exhaust note, then once you re-connect the MAP sensor plug it should go back to normal. this proves the N75 is "alive", however it doesn't mean it's 100% working as there could be another fault, sticking in low duty cycle position for example.
How to adjust the VNT rod length
When these turbos are new straight from Garrett, the rod length and stop screws are setup professionally in accordance with their specifications. since they do not publish these specifications alot of re built, re manufactured, re furbished turbos do not have them properly set up. This includes so called "Garrett approved turbo re-builders" most of the time they will just leave them as standard and expect them to work, and they will work most of the time but obviously there is going to be times when they don't. And because the hybrid turbos are different specifications, the rod length and stop screw specifications from Garrett will no longer apply. this means the turbo must be set up either on a flow bench or on the car.
Adjusting the rod length is necessary if you are getting errattic boost problems, if your duty cycle is above 80% at 4,000rpm then it needs made longer, and if your duty cycle is below 70% at 4,000rpm it needs made shorter. between 70-80% is ok, the closer to 80% the better.
How I do it is remove the TIP and get at it from above, it is possible to do it from below but theres limited space down there too, I prefer the top way.
so once you have removed the tip, you will be able to see this-

vnt5.jpg
I always remove the c-clip that holds the rod onto the vnt lever, it means you can push the rod off the lever as far is it will go right before it hits the compressor housing and you can then get your thumb in where the red square is to move the knurled ring and adjust the length.if it's a brand new turbo you might not need to do this because the rod will still be new and oiled, but on a 5 year old turbo they tend to be seized a bit, so this is why you need more room to get your whole thumb in there and get more purchase on the ring.
to loosen the 10mm locknut, best way is to cut a 10mm spanner as shown:
dfb068d8.jpg
if you try and use an open end, the jaws are too big to get onto the nut, so you need to cut a slot in the ring end, and also chop it in half because theres limited space between the bulkhead and the engine.
heres a pic of the spanner in use and what you will see from above:
738c47d4.jpg
adjustment should be done one turn at a time, and re check with VAG COM after adjustments.
How to cure sticking vanes
If the vanes are sticking, firstly you can try removing the actuator/VNT rod and giving the VNT lever a bloody good wiggle, it's not garanteed to fix the problem but it worked for me years ago! To do this you need to gain access to the turbo either from above or below, remove the 2 X 10mm nuts holding the actuator to the mount, then remove the C-Clip holding the VNT rod onto the VNT lever, and then you can slide the rod off and remove the actuator alltogether. once it's out of the way, give the VNT lever a good wiggle and then re-fit and see it it has cured the problem. if it doesn't work then you could either do a DIY refurb, you could send it away to a company to get it re-furbed, you could try using a boost valve, or you could attempt the Innotec VNT clean. more info on all of them below
Refurbish the Turbo
probably the most expensive way, most companies will charge about £250 to do this, maybe more. also be aware that it might come back with a new (incorrectly set up) actuator/VNT rod. you could also do the clean yourself if you are competent, heres a guide: http://pics.tdiclub....edure_small.pdf
Using a Boost Valve
here I have found a quote from myself about a year ago, this can work and help stop sticking vanes, however I would not use it for any other reason, i.e to stop spiking or mapping issues. I used one to stop spiking a year ago, it cured it a little bit but the problem was still there, allbeit masked a little.
the reason it works is when the duty cycle is raised, the actuator sees less vacuum and the springin the actuator is expeced to return the VNT lever back to open the vanes up. so it's not a force acting upon the actuator, but instead the abscence of a force and it's all relying upon the spring. if the vanes are a little bit coked up, then it might stick or not respond as quicky as it should, so what this method does is put boost into the vacuum line, which has the opposte effect to the vacuum and will open the vanes up instantly, resulting in lower boost. It basically gives it a bit of a kick.




Innotec Turbo clean
I don't have personal experience of this, but I am told it works. more info on this thread https://uk-mkivs.net/...s/t/230403.aspx


Sent from my GT-I8190N

#411 Kaos85

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Posted 04 September 2016 - 09:11 AM

Can anyone tell from my graph if I need to adjust the actuator rod??
Anyone?? Help would be seriously appreciated as been having a nightmare with this issue and the arrogant mapper I thought I could trust has clearly screwed me over! :(

#412 martinlink

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Posted 28 September 2016 - 01:05 PM

Can anyone tell from my graph if I need to adjust the actuator rod??
Anyone?? Help would be seriously appreciated as been having a nightmare with this issue and the arrogant mapper I thought I could trust has clearly screwed me over! :(

It seems that your stop screw is way too long and you'll have to unscrew it by at least 1 full turn, if not more.
Actuator seems to be about right, maybe 1 turn shorter but start from the stop screw.

I had a very similar scenario where boost came in very late and faded off in the end. It turned out to be the housings that were worn, so the air could bypass the blades and not create adequate pressure.
I will post my graphs with the old and new housings if anyone's interested. My graph isn't perfect yet but it's 200% better than it was with the old housings.

 



#413 marijo25

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Posted 06 April 2017 - 02:34 PM

good day

 

i come from croatia. i drive golf mk4 tdi ajm code of engine.(chip tuning from ABT)

recently i change my turbo charger. now i have safe mode in 5 and 6 gang uphill over 3000

 

i made test in vag-com. one in 4 gang uphill and second in 3 gang straight full throttle

 

d cycle in booth case came to 94,4 %

 

i think that mehanic did not propertly adjust actuator?

 

thnx in replay

Attached Files



#414 clintoncoetzee

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Posted 23 August 2017 - 04:02 PM

thanks, very useful post. cant seem to see your pics though



#415 Rgm36

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Posted 13 April 2021 - 09:53 AM

Hi there folks, I hope you don't mind me resurrecting this old thread, but rather than posting a new one this seems to be the official thread for my current problem!

 

I'm trying to get the actuator rod correctly set, my PD130 ASZ had a replacement turbo years ago and I don't think it was ever correctly set. Having been off the road for some while, I've just replaced the VNT actuator as the old one was fubar. I've got a full version of VCDS and can log etc, but I have a question before I post graphs etc on here as I'm struggling a little to achieve consistent results. What exactly is the procedure? Is it written down somewhere? I've been keeping it below 2000 revs then flooring it in 3rd, pedal to the stop, until it hits 4000 revs. I always allow the engine to achieve warm temps first. Many thanks.


MKIV Golf TDI130BHP, Broken!






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