Un-Sticking Your TDi VNT Turbo Vanes.....

How hard is it to remove the actuator arm so that I can test the actuator arm, if its a total nightmare I will use long nose pliers, thanks in advance, Ste :)
 
Based on similar Garrett t/c on different car:
The actuator bellows has the vacuum tube entering one side, and the pull-rod coming out of the other side. This pull rod then drops down to the actuator arm on the bearing side of the turbo. So if you grab the actuator bellow like a ball, you should find the actuator shaft between your fingers, and you can then squeeze to pull the actuator up.
Should move with less force than a tennis ball takes to squash, and then drop back to fully relaxed. If you hear air hissing, you might have a vacuum leak (tube) or a problem with the actuator (most unlikely).
The vacuum is modulated by a trembler valve (identified as N75, above), so you get the amount of vacuum to achieve the scheduled turbo boost; if the control reaches full range without getting the boost, then the fault will be reported.
Note that only the VNT/VVT is in the hot area; the actuator is almost 4" away, so much cooler, and the electronics of the trembler valve are well away from the hot area.
HTH,
Tom
 
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very well put Tom.

Folks, what sticks, is the ring the actuator operates on, and it usually sticks in the full boost position with the vanes closed (well pointing to the hotwheel / exducer) - hence when you use MM to soften and absorb the carbon, you should be able to get the actuator arm moving (which is actually moving the vnt ring and vanes inside the hot end. (MM = Mr Muscle)

And its only needed if you get over-boost limp mode, on a VNT turbo diesel.

also, never ever put MM in the intake side of the turbo!!! it reacts violently with aluminium and produces a toxic gas, never get it in contact with alloy. At least MM has a lower concentration than you may have made yourself, I never went into that before but you can make a strong version for pennies if you find MM cant shift the carbon cos its so thick....MM is Sodium Hydroxide, otherwise known as Lye, or Caustic Soda (as used in Biodiesel production - key element for de-soaping the veg oils) - you can buy caustic soda crystals in a number of places, and read the instructions. Always add the crystals to water, never the other way round, and wear goggles, gloves (and an apron if your a clutz) and inject the solution using a plastic paint mixing syringe and follow the original instructions after that.

Sodium Hydroxide burns hot too so when it gets blown thru the cat, whats left of it ignites and helps clean off the mesh as well. My cat was cleaner than before after doing it. Its the only substance known to man which can dissolve carbon into itself apart from a chemical mixture called Piranha Fluid which is Hydrofluoric acid, and Sulphuric acid, a VERY VERY nasty combination, that even eats glass. Its used to clean carbonized glassware in a chemistry lab.
 
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Always add the crystals to water, never the other way round, and wear goggles, gloves (and an apron if your a clutz) and inject the solution using a plastic paint mixing syringe and follow the original instructions after that.

Slightly worried about suggesting the use of this, especially if someone is a klutz!
Also, it is typically better to try two iterations of a slightly milder (and safer) solution, because the effect is cumulative.
But I agree with all the rest of your comments, and thanks for your kind comment.
 
lol cheers man, I'm an electronics engineer, in process control & automated machinery so I have worked in a few chemical plants or similar like paper mills, power stations etc and so you have to find stuff to work in some difficult areas, they use a list of preferred chemicals for certain tasks, like decarbonizing a large steam plant boiler tubes in a firebox. Thats how I found out about Sodium Hydroxide shifting carbon.

The MM foam is easy to use if you get the bit right with the tubing (get it to the bowels of the turbo cast iron end) and get the foam to fill the hot wheel casting (brown cast iron end again for those that arent sure.)

So to summarize, fill your brown end right up with foam so it touches every part of your ring and soaks your nozzles.

(ooooh suits you Sir!)

1267092318 paul whitehouse suitsyou

I've got it on my skin before and it doesnt burn readily cos its like 6% NaOH if you rinse it off fairly soon, but it works well after a couple of hours on the turbo. Too long, and its solvent evaporates and it starts to gel, if you do that by mistake then just add another filling of foam, wait an hour and then button up and blast it out on a run. The new stuff will turn the gelled stuff into liquid again pretty quickly.

Raw caustic soda in pure concentrated liquid form is EVIL kids, its really bad stuff that instantly dissolves eyeballs and noses, it's as dangerous as sulphuric acid , its just at the opposite end of the PH scale. It turns body fat instantly to soap (true, thats how soap is made - chemistry lesson 2 LOL)

Use the MM foam ok. Don't make your own.

Walterwhitequotebreakin
 

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lol cheers man, I'm an electronics engineer, in process control & automated machinery

So that's why we speak the same language; I'm a system engineer, coming from a software background, working in avionics, so describing a process, and understanding the reasons behind it, are my bread and butter.
Strangely, this forum doesn't seem to be too wrapped up in the electronics controllers, and is biased towards mods and basic mechanical stuff, which is good. Just moved over from another forum (changed car) and there it was all codes and diagnostics.
Anon
 
lol I get ya. I just like tinkering with 90's TDI's but sometimes things need more explanation. I try not to be too stuffy and have a laugh tho.
 
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Evening,

Just out of curiosity, would it be a better idea to get a blanking plate with a hole big enough to insert the 3mm silicone tube, cover the turbo from the exhaust side and fill it with Mr Muscle? This method apparently is also used, when using innotec.
 
That's essentially what I did with my 2.5TDis.

Three nuts to unbolt the exhaust, tuck the tube behind the turbine, squirt and cover with cardboard - before the foam jumps out.

A lot easier than trying to feed through and the result was still a freed-up actuator.

Regarding Tolaks comment,
As I see it, codes and diagnostic computers should be regarded as one more tool to assist in the driving experience - along with tape,penetrating oil and big hammers!
 
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That's essentially what I did with my 2.5TDis.

Three nuts to unbolt the exhaust, tuck the tube behind the turbine, squirt and cover with cardboard - before the foam jumps out.

A lot easier than trying to feed through and the result was still a freed-up actuator.

Regarding Tolaks comment,
As I see it, codes and diagnostic computers should be regarded as one more tool to assist in the driving experience - along with tape,penetrating oil and big hammers!

Agree about using any hole to get the foam into the turbine. However, the inlet manifold upstream of the EGR and especially the head (upstream of the exhaust manifold) is aluminium, and so will be damaged if you put too much foam in, so the foam content needs to be measured/controlled in some way. Using top-down is easier, since the exhaust is steel, and only spillage upstream of the turbo is an issue.

Driving experience, absolutely. But some of the issues are diagnosed with codes, and some with good old-fashioned mechanical skills, so those problems need everything we can use. Working out what the problems are, so all that remains is the "simple" repair, is the preferred route; these garages who swap one component after another (charging you at every step) are just making a mockery of diagnostic skills, and the customer's wallet. I would be much happier if they bore the costs of items found en route, so they could claim the benefit of their skills.
 
I have recently had this problem with my 1998 Audi A4 1.9TDi the Mr Muscle worked a treat on it.

Many thanks for the info.

Colin
 
Sorry to revive an old thread but did your car have an egr cooler? What engine type was it? Bkd? My aluminium pipe goes from the egr valve to the egr cooler and then there's another pipe that goes from the cooler to the turbo which is extremely hard to get access to from the top and i tried already from underneath the car but the frustration got to me so I want to try another attempt from the top regardless of how long it takes
 
Sorry to revive an old thread but did your car have an egr cooler? What engine type was it? Bkd? My aluminium pipe goes from the egr valve to the egr cooler and then there's another pipe that goes from the cooler to the turbo which is extremely hard to get access to from the top and i tried already from underneath the car but the frustration got to me so I want to try another attempt from the top regardless of how long it takes
mine is 53plate, so has same cooler as yours, to get easy access like on those pictures i had to completely remove it (left it hanging on rubber pipes only).
 
Just abit of info. Did this on my car 13months ago (~5k miles). Mostly driving on cold engine round town so turbo gets covered in that soot really quick. had to do it once again now because limp mode appeared again couple weeks ago. Well, this time it was much quicker because i knew what i am doing this time. Thanks once again to this topic owner. saved another ~£200 for turbo cleaning? :)
 
i've been trying to solve the dreaded limp mode problem with my 97 1.9tdi i had high hopes after reading this thread. I thought everything went well. The pipe went downwards as much as i expected it to. But no change i was expecting a plume of smoke after starting up but there was nothing??

Maybe the pipe did not go where i expected it to?
 
A million thanks for these posts!! This should be required reading for anyone with a TDI! Could not get the actuator arm on my Merc Sprinter 212d to move despite best efforts. Found post re using Mr Muscle and gave it a try. Still no movement. Needed to go out to shops after spending much time trawling internet and trying various things, so off we set with the van running like a pudding and making an horrendous clacking noise from the engine. As we get into town, about 5 miles away, the clacking noise starts to change in tone but the EDC light that had been on permanently for almost a week stayed on and still no real improvement. Shopping done, we climb back in and I fires up the engine. Couldn't believe my ears or eyes. EDC light out and turbo boost back to normal. Boy, did I enjoy the drive home!
 
Hi All!

I would like to thank everyone who submitted in this post so far for such a great DIY solution. Of course I'm fully aware this would not resolve a problem (limp mode) as it would when mechanically clean a turbo and can be back more sooner than later. But here's my (succesful) story.

Back in Sep'13 after stuck in start-stop traffic in London for a long time I've decided to give my Audi A4 ('02 AVB) a good burn out when accelerating on slip road. When did I've suddenly felt lack of power? No error on dashboard? That gave me idea that boost was not there. After a mile pulled over onto service and stopped the car. After examination what’s under hood (any leaks maybe?) I’ve started the car once again. Voilà! There’s a boost. Back to normal driving but without giving a heart attack to my horses. When doing high rev’s on motorway there wasn’t any issues. Forgotten… Until one beautiful day in June’14 limp mode kicked in. Accelerating with foot down was not a way to go anymore. Error code from ECU confirmed: Positive Deviation. Later changed vacuum tubes, N75. Nothing. I looked for any solution even taking the turbo out and sending it to experts. But £300+ expense was not an option cause lack of funds. Had to do it myself or I could damage the engine or cease the turbo completely. Then this solution pop-up in search results.


Was a bit sceptic about injecting anything “foaming” into turbo but answers from technical-minded people proved me that there’s a small risk of damaging unit if done right. My concern went down to only one thing. Could amount of carbon buildup detaching from inside could have negative effect after reving an engine for first time? …

Give it a shot anyway. Took EGR feed pipe off to get access to exhaust manifold. Took tiny plastic pipe from everyday sprayers (household cleaner) and attached it to Mr. Muscle and other end down into turbo hot side. I sprayed in 1 sec shots until foam buildup could be seen through pipe entry. Took everything out and proceed reattaching pipe back. Took me about 30min to do so. Enough time to solution work it’s beuty. When tried to move turbo’s actuator arm it didn’t until about 20min after spray. Happy! Started car, cycled revs 3k-to-red for about 30sec. Then I took car for a trip. No more limp mode kicked in. Bless!!!

Whole operation took me less than 3h, couple of adapters and strong will not to take anything but only air intake ducting!

Photos:


I will repeat this operation probably once every 5k miles or 6 months to keep it in shape.

Thank you very much again and let your turbo live long.

Seb
 
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Hi,

I've been trawling these threads in search for the best way to insert the Mr Muscle into my turbo but cannot find any suggestions for my engine type. I have a 2006 A4 2.0 TDI (B7 chassis, BRE engine).

Any threads or photos I have found are not for my engine. I know the process will be similar; however I want to be sure I get the cleaner into the correct part of the turbo before I go ahead and do it.

Any further suggestions or photos for this engine type would be greatly appreciated.

Cheers.
 
Probabbly a silly Q is N75 in this pic the MAF sensor? and is it ever the cause? been told turbo boost solenoid naffed and did ask them to clean it out n vac hoses n been told be cheaper to fit new turbo!! would a dodgy MAF send wrong signals to ECU or is my turbo sticking too? have been to garage first they reset ECU n said would be fine so proved point of going straight to motorway to show them it solved f all :(
I'm sure I took pics but havent put them on photobucket, will get some up asap tho matey :)

Here is the bay, the crinkly pipe running vertical is the egr pipe, joins the exhaust mani on the bottom with the inlet / egr valve at the top:

Photo-0017-2.jpg


Here in this diagram you can see the exhaust manifold and the egr hole on top, see how it runs down into the turbo, its the only downward hole, visible thru the outer egr hole with a torch: (our UK turbo actuator is up the other way but the manifold and cast iron side of the turbo are the same)

turbo_tdi_N75_N18_N239m_EGR_VNT_Act.jpg



This pic shows the route you want the tube to take quite clearly to enter the turbo on the exhaust side,from the egr hole with the 2 studs, thru into the turbine housing. (never put anything in the intake (alloy) side, only the cast iron half). This is not the exact same as ours, its a vnt20 but close enough for illustration purposes:

12052009357-1.jpg
 
I know this is an old thread but this seems the place to post my question.

My 1999 A4 1.9tdi (230k) began to become very sluggish with the turbo only functioning occasionally. After checking for and leaks I decided to try the MM clean, I followed the well detailed instructions and to my delight when I pulled off down the road a few black dust clouds appeared from my exhaust and full power was restored more than the car had previously had in my ownership. The car continued to drive well for a couple of weeks after. Then it started to go back in to limp home mode and now the turbo is not functioning at all and the car makes a loud clacking noise. Power is right down. I repeated the MM clean twice more in the hope that this would help, no improvement.
the curious thing is, If I start the car and floor it round a left hand bend the turbo will kick in and will remain active until about 3.5k revs or until I let it drop back to much lower revs. I'm not sure what to check next, I can't see any possible leaky pipes. Can anyone suggest what tests I can perform and why do I get the loud clacking noise?
 
I know this is an old thread but this seems the place to post my question.

My 1999 A4 1.9tdi (230k) began to become very sluggish with the turbo only functioning occasionally. After checking for and leaks I decided to try the MM clean, I followed the well detailed instructions and to my delight when I pulled off down the road a few black dust clouds appeared from my exhaust and full power was restored more than the car had previously had in my ownership. The car continued to drive well for a couple of weeks after. Then it started to go back in to limp home mode and now the turbo is not functioning at all and the car makes a loud clacking noise. Power is right down. I repeated the MM clean twice more in the hope that this would help, no improvement.
the curious thing is, If I start the car and floor it round a left hand bend the turbo will kick in and will remain active until about 3.5k revs or until I let it drop back to much lower revs. I'm not sure what to check next, I can't see any possible leaky pipes. Can anyone suggest what tests I can perform and why do I get the loud clacking noise?


Hello JBH n Rusty, i did HAVE ECU red n they said they turbo solenoid fault which was probly the actator sticking, got a friend to hAVE A LOOK AS HAD 300 mile trip for work to do n when he took egr vALVE OFF WAS COMPLETELY Clogged in crap he scraped out most of it n 60 miles in n and pluuing over twice limp mode stopped :O) since been back been fine round town but had 180odd mile trip this weekend n as soon as i hit motorway back to limp, have ordered a new solenoid n EGR valve off ebay so watch this space will tell you if it works, just need a good run daily i think too to stop it clogging i do bout 5 miles to my sons school n work n back,, needs a proper boot daily i thnk! hows yours going now???
 
Had sticky vanes on my seat toledo tdi (asv engine), which resulted in 17965 - Charge Pressure Control: Positive Deviation fault code. Used this method today to solve the issue. The manipulations were a bit different from those described by topic starter as the engine positioned across the bonnet in Seats, so the turbo is behind the engine. Will write my DIY here just in case any Seat Leon/Toledo owners google this forum.
I had an error code 17965 appearing as described above and TCS light came on after about 10-15 min of driving. Read up on forums that it might be caused by sticky vanes in the turbo. Decided to check if the vane actuator moves smoothly by unplugging the vacuum line from N75 valve (the passenger side one with the grey head) and applying vacuum with my mouth (I would recommend proper vacuum pump though). It did not move much but I could push the actuator rod with a finger all the way down. However there was a particular position where the movement was really stiff and I could feel the vibration on the rod like the vanes were scratching something. The interesting bit about my case is that the fault came up only if I drove in slow relaxed way, without sharp accelerations and stuff (some call it granny driving style, I prefer to call it limo driver style :))). However if I drove the car like I stole it, there was no problem at all, only when I drove slowly. Presumably the vacuum in the actuator was not strong enough to move it at low rpms and the vanes got stuck creating problems with boost pressure.

Anyway, decided to try evilscotsman's Mr. Muscle trick to clean the turbo. As I said the engine is across the bonnet in Seats and turbo is located behind it. I could see EGR hole and could possibly open it up, but there was no way I could look inside to control how much cleaner I put there. So I had to go through the exhaust output. It is a bit tricky (but doable) task as there is not much room behind the engine, lots of different pipes and wires which restrict the wrench movements. You can not really see the nuts there but you can find them with your hand and unscrew blindly. Don't be put off with it, as I said it is feasible but fiddly (I spend ~30 min to unscrew it and half of it to screw it back). There are 3 nuts there (13mm socket), which are obviously rusty and seized, so make sure you generously sprayed them with WD-40. To get better access to that area I removed big plastic air pipe from the air filter. The exhaust pipe is flexible there so you need to undo just those 3 nuts and you'll be able to move the exhaust pipe aside. There is steel gasket sealing the junction, I reused it without any problems, it actually looked very well (not brand new, but not rusty or damaged). Removing the exhaust pipe opens the access inside the turbine where I sprayed Mr. Muscle and clogged the hole with the plastic bag. I am not sure if NaOH can dissolve any plastics so test it first on your plastic bag if it withstands Mr.Muscle treatment. I first sprayed it for a couple of seconds (no extra piping was needed just sprayed with standard nozzle), then I turned turbine few times with the finger (wearing rubber gloves!!!) and than gave another short spray and clogged the hole. After about 20 min I tried to suck actuator pipe again and pressed the rod with the finger. Initially, the movement was still a bit stiff but I could feel how it got more and more smooth. Left it for another 15 min and repeated the operation. The actuator was not stiff any more and had smooth free movement all the way. Then another 15 min and repeated actuator exercise. After another 15 min (1 hour altogether) I tried actuator again, it was absolutely free and smooth, I could move it all the way down by just applying the suction to the vacuum line.
Assembly was in reverse order (put the gasket on, put the exhaust pipe on, screw the nuts back and put the air piping back). It was easier but still bit fiddly as I explained above. I was be able to put nuts blindly with my fingers first and than finished it with a 13mm socket wrench.
After that I turned the ignition on and give her a spin with sharp accelerations and high revs, cleared all fault codes with vag-com, and drove her in my usual limo style :). So far so good, no faults stored in ECU. Will rev engine up every now and then to prevent vanes sticking again.
Hope that will help to someone else.

Many thanks to evilscotsman for such a great method for cleaning the turbo.
 
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Hi - I purchased a MK5 VW Golf GT TDI (140) last week and I've being experiencing limp mode on it in 5/6th gear at 3000rpm when it hits about 80mph. I've taken it to a garage who have stripped the turbo and cleaned it, put it back together and I'm still getting the same problem.

I've been reading all sorts of forums and have now come across this 'Mr Muscle' one and noticed it has helped a lot of people! The garage have had another look at it and have had their VW guy look at it also, saying its the same problem and that it's sticking, so the valves/pipes aren't closing properly (not sure if that's the correct terminology - I'm a lay man when it comes to cars, forgive me).

My question is if it would be worth doing the MM trick if the turbo has just been 'cleaned' by the garage?

Apologies for the inconvenience and thanks for your time
 
mine is 53plate, so has same cooler as yours, to get easy access like on those pictures i had to completely remove it (left it hanging on rubber pipes only).
DeNi, so you completely removed the egr piper that goes to the cooler from the her AND the egr cooler itself???
 
DeNi, so you completely removed the egr piper that goes to the cooler from the her AND the egr cooler itself???
Yes,2 allen bolts on front of cooler, and 2 allen ones under it which conects cooler to that pipe which goes to exaust manifold. And another few small ones which holds cooler at that place. They are under it, which is abit awkward to get to but manageable.

This pictures are not 100% the same as egr looks different on ours, but from them you can see all you need,refer to 5th picture : http://www.myturbodiesel.com/wiki/intake-manifold-intake-flap-or-egr-removal-b5-vw-passat-tdi/
 
Sorry to bring this thread back to life, hoping someone can help! Feel like I've cocked up big time here.

I've just done this today, I wasn't experiencing limp mode before but I wasn't getting full power from the engine and a few people suggested trying this trick. All went to plan, or so I thought - went for a drive after leaving it for an hour or so; limp mode straight away. I drove nice and easy for a few miles until it had warmed up, then tried to rev it to blow the crap out of the exhaust, I didn't see a lot of smoke come out. I smelt burning in the cabin, I assumed that was the oven cleaner?
After a few more miles, my engine management light came on and told me to 'STOP - Brake fluid'. Not good, I'm panicking now - anyone got any ideas?
 
I've got a 1.9 TDI Leon which I want to do this to. Obviously the engine layout is different to the Audis - anyone got any idea if I remove the EGR valve, if the small pipe to the left of this picture is the one which I need to insert the silicon tube and oven cleaner into? Really fiddly access on the 1.9tdi...
Mine is a 2007 model and the photo is a gallery one of an earlier Leon. However, the layout on the newer model seems similar and I can't find anything else to compare it to.
Thanks in advance!

20141005_182809.jpg
 
might be easier removing the downpipe on the leon? But yes, that stainless flex-pipe leads to the exhaust manifold
 
might be easier removing the downpipe on the leon? But yes, that stainless flex-pipe leads to the exhaust manifold
Thanks for the info. Are you able to expand on that a bit? Wouldn't I just be able to drop the silicon pipe down the flexi pipe in the photo to feed straight into the turbo?
 
If anyone in East anglia who's handy with a spanner could help me do this I'd be more than happy to offer some beer tokens. Thanks

Sent from my D6503 using Tapatalk
 
Sorry old thread I know but its exactly what I need to do any idea how to get the pictures to show instead of the photobucket ransom sh##e
 
My god, after 8 years this fix is still doing the rounds online and working well. Superb! I keep seeing videos on YouTube too, keep up the good work folks, just saw the thread linked on another forum and thought I'd drop in and say hi.

Cheers,
EvilScotsman ;)
 
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