Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!!

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Thu 5 Oct 2017 09:20
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - Graeme Bain
Hey all, first things first, I'm not sure how to put a new comment as I'm a newbie!!, but I have a similar problem, sometimes my car cuts out under high load, 50-80mph, turn ignition off and back on and it's fine, if it happens enough then I get a light on which I've diagnosed and it comes back as "Overboost", the car apparently had 2 intercooler hoses replaced with new clips too, it had a 180 map on it which was horrible and causing a overboost fault, it's been carbon cleaned and turbo flushed 3 times as the vanes were jamming open, then it had a 160 map put on it.. I'm aware that these cars can take up to 220bhp before serious modifications are required. I've been to a few people who haven't even looked and said turbo is b*****ed and went to a garage and said the same, have had other people give there opinion and said it's everything from N75 valve, diaphragm on the turbo actuator, the actuator itself, but I'm still driving around in it....no black smoke, powers there... it hasn't cut out in about a week or 2... I have tried loads from putting 2 stroke in with the fuel, to engine flushes, the lot... I don't want to throw any more time at it as it's so frustrating, I've heard it can perminantly damage the engine, I noticed a leak on the intercooler hose where it meets the intercooler, its noticeable when I'm driving the boost noise, I've left it in hopes that it lets enough out so it counteracts the overboost and stops engine failure, just hit 100k and done 800 mile runs where it hasn't happened, but under load increases the risk of it coming back, I don't know what to do anymore, I'm worried that the turbo will s*** the bed, we have just had a newborn and we rely on our car, we are worried that the turbo could die any day... anyone able to help??.. thanks

Graeme
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Thu 5 Oct 2017 09:22
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - Graeme Bain
I also forgot to say that it doesn't run the smoothest on idle, sounds almost lumpy sometimes, soon as you touch the throttle it's perfect, the more you idle sometimes the more lumpy it runs, weird as f***..
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Thu 5 Oct 2017 09:50
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - focussed

" we have just had a newborn and we rely on our car, we are worried that the turbo could die any day... anyone able to help"

If you need a reliable car, why did you either buy a car that had been messed with or mess with it yourself?

Get it put back to standard and then sort the problems out from there is my advice.

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Thu 5 Oct 2017 10:18
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - Graeme Bain
I bought this car with the only thing I seen was that the intercooler hose was knackered and needed replaced!... it ran fine for a while with no issues, as far as I'm aware is that it is back to standard, feels like 140bhp over 160bhp, the question I'm asking if you didn't read the thread is what is the problem so I can sort it!, thanks

Graeme
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Thu 5 Oct 2017 10:56
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - RobJP

If it's the Mk 5 Golf, then it's the 2.0 TDi engine, which is notorious for problems.

As you yourself say, it's had various modifications and chipping done to it - as you say, a 180 map, then a 160 map, and now you think it 'feels like' it's back to the standard 140 (but you don't actually know if it is or not).

Basically, that engine (and that generation of Golf) are well-known for being a bit of a dog's dinner of a bodge. I'd suggest a diesel / independent VW specialist, and if they can't help you then get shot of the thing.

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Thu 5 Oct 2017 11:00
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - Graeme Bain
Yeah, these engines are unreliable ... everything runs well apart from this cut out problem, I'm just trying to find out what it is... I don't have the time to be able to advertise and sell, then search for a new vehicle, we are quite remote so we need a vehicle everyday... I've been to a Vw specialist who can tell give me anymore information than I already know, apparently the turbo is faulty but it's working?, thanks
Graeme
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Thu 5 Oct 2017 16:50
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - Graeme Bain
Bump
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Thu 5 Oct 2017 22:15
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - Peter.N.

Take it to a diesel specialist, they usually know what they are doing.

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Fri 6 Oct 2017 11:07
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - Graeme Bain
Been and tried... paid £60 to get the car diagnosed, came put with the exact same code and information as my £20 diagnostics kit, and said the turbo is probably b*****ed.
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Fri 6 Oct 2017 20:47
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - sandy56

If you can the car to a standard state of tune, and if necessary you can get the turbo reconditioned/ exchanged, but use a reliable "named" supplier. There is a lot of bandits around.

But first you need a good diesel mechanic to check it out.

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Fri 6 Oct 2017 22:15
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - Graeme Bain
That's my problem, I have been to about 7 mechanics, all have said different issues, and the Vw specialist said the turbo is knackered, but works well, no smoke, no nothing.. a new turbo is something that is expensive with a newborn, but if it fails then I will replace, I just want to know is it definitely that, and will leaving it as is do damage, I get overboost code and cut out once a blue moon, if you drove it today, you wouldn't know anything is wrong, it's only because it's happened a few times before that makes me wonder... thanks
Graeme
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Fri 6 Oct 2017 22:17
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - Graeme Bain
Does anyone know what values should be to determine a faulty or working turbo, I have VCDS LITE and the cable to hook up... but I don't know what I'm looking for on the software...
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Sat 7 Oct 2017 00:43
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - Railroad.

Your problem sounds like the very common sticking turbo vanes. A new turbo is often not required. They just need a good clean. I've used Innotec Turbo Clean a few times and it's always worked. One piece of advice of you use it. Do it when the engine is cold, and follow the instructions. It'll feel like a new car afterwards.

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Sat 7 Oct 2017 01:06
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - Graeme Bain
See that's sounds like a plan, I have thought of that but have been informed that the turbo will never be the same afterwards.
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Mon 9 Oct 2017 12:27
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - Graeme Bain
Although I was wondering, the old owner has said he did a turbo flush?, could they be lying?, or is there no garauntee that it will work and I may actually need a new turbo??
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Wed 11 Oct 2017 12:47
Mk5 golf Gt Tdi - Mk5 golf Gt Tdi turbo issues, help!! - dieselnut

I've had this problem ( overboost ) on a previous Passat, caused by sticking vanes in the turbo.

Innotec wasn't around then, but if Railroad has had success with it I guess it must work.

I took the turbo apart & cleaned the carbon dust out.

The thing is that the variable vane mechanism is in a void inside the turbo. The tiny carbon particles get into this void & clog up the mechanism.

If carbon particles can get in there then Innotec can also get in to clean it.

But the carbon took many thousands of miles to build up in there & the Innotec has just a few seconds to do its cleaning work. So I think it will only be a short term fix. Can't see how it can remove all that carbon.

Anyway have a look at this link to youtube. It may not be the exact same turbo as you have but they all work in the same way so will give you a guide to what is involved .

I would plug the turbo oil ways before you take it apart to avoid any contamination getting into the bearings & put plenty of clean oil into the bearing before re-fitting.

www.youtube.com/watch?v=WJ6Ckad632I

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