Really strange whinning whistle coming from turbo, limp mode twice!!! a3 2.0 tdi 140

chrisy t

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This past week i have noticed a funny whine coming from the engine when you rev high and then let off the revs it make a loud whistling noise, its quite strange, also i was overtaking in 5th gear and lost power went in to limp mode, stopped engine and started again and it boosted fine!, last night i was powering up a hill in 4th gear and agin it went in o limp mode! ive been reading some threads on here about the turbo failing! Sticky veins? what is that? i usualy do all the work on my car so, would it be worth me taking the turbo off and cleaning it up? what do the veins look like and can i just use brake cleaner to clean the turbo? Any help on this would be much appreciated.

Cheers
Chris
 
It does indeed sound like the VV turbo has failed. Had a couple at work do this (Golfs in our case). In basic terms, the turbo is a variable vein type which means they are moveable. They carbon up and stick. The turbo is cleanable if you remove and strip.
 
sticky vanes are from VNT turbos, all that essentially means is there is a lever which is pulled through vacuum hose which varies the amount of boost and different loads, it does this by changing the 'shape' of the internals of the turbo, creating more/less flow. if you google vnt turbo there is loads describing the inner workings. the problem arises in the general design of the turbo, it is powered by the exhaust gas, the lower the rpm the slower it spins, higher the rpm the higher the boost. Now a diesel exhaust gas is fairly dirty, lots of carbon gets chucked out the engine. this carbon clings to the variable parts of the turbo, which make them stick in one position, the car can no longer vary the boost, resulting in an under/over boost code putting the car into limp. I believe innotech do a clean kit for about 50 quid. this is a 2 part process first to dissolve the carbon, second a clean/lubricant. used this kit once worked great on a vw i owned, prob came back and i then just used mr muscle oven cleaner instead. what you do need to be wary of is the egr valve, in my last car i didnt block it off so the fumes got pulled back into the engine and went mental. Brake cleaner wont do too much to the carbon deposits (unless you strip aprt the turbo and can scrub a bit) have you scanned the car using a vagcom? dont do any work until you know what exactly caused your limp mode.
 
Ive not scanned yet no but i will do. im convinced its the turbo though, i mean might be worth jut giving it a clean anyway? I had my egr off about 3 months ago and cleaned it with brake cleaner, it was full of gunk!! It seemed to go much better once i cleaned that, you dont think that could have anything to do with it do you? Is there a guide to taking the turbo off or stripping it and cleaning it, i just wouldnt like to damage it, ive heard people say you would need to drop the oil to take the turbo off, is this true?

Cheers
 
Forget innotech if you want longevity, its crap by many reports as its not very thorough or hasnt worked at all, get it scanned 1st & I would say it will show overboost errors given your description, so turbo of, clean or replace with same or hybrid version.
 
Had it scanned, came up with overboost intermitent, also mass air flow sensor. However i had the MAF unpluged while car was running a few weeks ago so could be that? Im thinkin about taking the turbo off anyway and stripping it and cleaning it for peace of mind, couldnt hurt could it?
 
With all your issues, doubt its maf, clear errors, test again, but you're running risk of turbo blowing, still advise take turbo of.
 
Really, do you mean by thrashing it i a running the risk of blowing it? or do you mean i am running the risk of blowing it just driving normaly? By taking it off and cleaning it could this help stop the turbo from blowing up? Im a little worried now lol!! Is there any diagrames on taking the turbo off and cleaning it, can i damage it by taking it off and do i need to buy any parts or replace anythingthat i take off?
 
The inside bearing went in mine and this happens. cost me £1146 to fix. did need a pipe aswell though
 
Really, do you mean by thrashing it i a running the risk of blowing it? or do you mean i am running the risk of blowing it just driving normaly? By taking it off and cleaning it could this help stop the turbo from blowing up? Im a little worried now lol!! Is there any diagrames on taking the turbo off and cleaning it, can i damage it by taking it off and do i need to buy any parts or replace anythingthat i take off?

Yes, if its overboosting then tbh it could go anytime, you need to keep it below 2000 revs so its not boosting as such, but imho you need to sort it asap, cause when it goes the oil empties out of the engine into piping, exhaust, makes a real mess, can cost anything from 1-3k depending on who fixes it.

I may have a hybrid for sale shortly.

did need a pipe aswell though

The pipe is only changed as an advisory, but if its not blocked when testing, then no need to swap out.
 
check classifieds im selling my turbo in 2 weeks
 
the innotech stuff WILL free up your vanes, NHN is correct though, it is only a temporary solution, the problem WILL come back. Its all down to cost, if you plan to remove the turbo, this is the best solution you do have to replace variety of parts, seals, banjo unions... i remember calling VW and the parts was coming up to the price of a new turbo :s I resorted to a monthly clean of the turbo. As i planned to get rid of the car i had so wasnt going to spend a fortune on it. So you could whilst costing things up run the turbo clean stuff just to temporarily get yourself going.
 
Should the turbo be quiet in a diesel though or should it make a little bit of a whistle/whine noise? Can always hear it whistle in my TT and my A3 does it too.
 
Ok then, were can i get parts from? can somebody give me a list of the parts i will need and prices? and i might just take the turbo off and see what i can do with it, if i take it off and clean it like by using sand paper cleaner etc will this help stop the turbo from blowing? Is there a detailed guide on how to take it off and clean it? Also, it has only thrown 1 over boost code error? If i do all the work myself can it still realy cost £1-3k?? seems alot, ive seen recon turbos on ebay for £300, is it not th case i could just buy one and fit it and that be me sorted??

Cheers
 
heared this wierd wistening noise on a 58 plate tdi sline with 50k would not rev over 2500k either when stationalry should i be worried?
 
Yes, if its overboosting then tbh it could go anytime, you need to keep it below 2000 revs so its not boosting as such, but imho you need to sort it asap, cause when it goes the oil empties out of the engine into piping, exhaust, makes a real mess, can cost anything from 1-3k depending on who fixes it.

I may have a hybrid for sale shortly.



The pipe is only changed as an advisory, but if its not blocked when testing, then no need to swap out.

It was cracked :/
 
How the hell did that get cracked, strange but yeah that would of needed replacing lmfao.
 
Forget innotech if you want longevity, its crap by many reports as its not very thorough or hasnt worked at all, get it scanned 1st & I would say it will show overboost errors given your description, so turbo of, clean or replace with same or hybrid version.

read the full thead and now i am wondering if my new one is the same ( just deposit on it at the miniute) is this possible on an 58 plate with 50k on it ?

i went to rev it when it was ticking over and it would not go over 2500K and made that odd noise ( not the same as my current turbo noise on mine) is this normal? i didnt give it the beans as the person from the garage was in the car with me.
 
My 2.0tdi started to sound like a siren and went into limp mode 3 times but drove normal. Audi replaced the turbo and egr valve as the bolts snapped under warranty, 90k but you do get a whistle but dont want the police siren noise.Showed up on scan. If I was paying I would try the advice already given, hope you get it sorted.
 
should it tick over in limp mode ?
had it running a miniute ortwo then tried to rev its nuts and it didnt go above 2500k
 
any one ?:whistle2:
dont wanna waste my money if the motors koed
 
yes should tick over in limp mode normally resets when u turn of and on again
 
cheers dude. are you upgrading turbo for speed or is yours guffed ?