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Model specific boards => Golf mk6 => Topic started by: PenguinGTI on 02 April 2011, 16:07

Title: Noise under acceleration
Post by: PenguinGTI on 02 April 2011, 16:07
Hi guys, looking for some advice about the car:

The problem

Some times when I am accelerating the car makes a funny sound. I don't quite know the word to describe it but it's almost like a squeak. It occurs only when I throttle.To narrow it down I've been keeping my foot on the throttle at various revs and the noise occurs just before the whistle of the turbo spooling.

At first I thought it was maybe the throttle but I can accelerate without the noise occuring. I don't know if it is the turbo or not but it definitely happens immediately preceding the turbo whistle.

Now my immediate concern is that the turbo might be going. I'm not experienced mechanically so I don't really know but my mind has jumped to the worse.
I woul expect however that if the turbo was going then I would experience power loss and also that the noise would happen every time. The noise is intermittent and sometimes I can go a few days without the noise happening.
Here are my questions:

Has anyone else had this noise?
Is this a sign that the turbo is going?
Is it perhas a belt or something that just needs lubricated?s
My car has now covered 40k miles

*EDIT I've been reading some on the internet who say that the turbo going usually produces smoke. There is NO smoke coming out my car if this helps with any advice.
Title: Re: Noise under acceleration
Post by: Buck on 02 April 2011, 16:13
I can only share my experience of when the turbo on my Audi was going and it sounds more 'dry' and rattley if that makes sense?

Certainly wasn't squeaky.
Title: Re: Noise under acceleration
Post by: PenguinGTI on 02 April 2011, 16:26
Yeah it's definitely not rattley.

The noise itself I woud say is more akin to a belt or pulley squeak but it only happens when the turbo is about to spool.
Title: Re: Noise under acceleration
Post by: The Doc on 02 April 2011, 19:39
Could be anything - what boost pressure are you running? bhp? Mods?
Title: Re: Noise under acceleration
Post by: GolfTi on 02 April 2011, 20:12
It's not the faint hissing sound is it?
On acceleration - 2 - 3 k lasts for less than half a sec.

Normal if it is.
Title: Re: Noise under acceleration
Post by: WILLS on 02 April 2011, 20:15
i get a hissing/metallic rattle between 2  - 3k i've been told this is normal
Title: Re: Noise under acceleration
Post by: PenguinGTI on 02 April 2011, 22:59
Doc, No idea what boost I'm running. Horsepower is around 260 odd with a stage 1 map.

There is definitely no power loss so I'm not entirely convinced it is the turbo.

I do know the hiss you are describing which if I am correct is the standard noise of the turbo spooling up.

The sound I sometimes get is altogether more like a squeal. It very much sounds like a belt squeal and I would assume it to be such were it not for it only occurring immediately before the turbo spools.

That having been said, drove home tonight and it didn't make the noise at all... just one of those typical niggles that only does it sometimes.   :undecided::undecided:
Title: Re: Noise under acceleration
Post by: RickS on 03 April 2011, 07:26
Yeah it's definitely not rattley.

The noise itself I woud say is more akin to a belt or pulley squeak but it only happens when the turbo is about to spool.

Penguin, you mention the "whistle of the turbo spooling". I've had several cars with turbos and none of them whistled, I don't think you should be able to hear the turbo from inside the car if it's working correctly, unless you've done a mod to make it audible.
I certainly can't hear it on mine.
Title: Re: Noise under acceleration
Post by: Snoopy on 03 April 2011, 09:43
Does it also make it if:
Your in neutral. You rev the car to ~3K then take your foot off the pedal?
Title: Re: Noise under acceleration
Post by: Exonian on 03 April 2011, 10:36
Any chance of recording the noise on your phone and uploading it so we can hear it? Would be easier to diganose that way.
I'll assume you don't have any uprated engine mounts or any other mods (dump valve etc)?
Title: Re: Noise under acceleration
Post by: JamesR27 on 03 April 2011, 20:41
i get a hissing/metallic rattle between 2  - 3k i've been told this is normal

Mine does the same as this between 2 - 3k and did take it into the garage but they said its normal.

Does it depend on how much you put the accelerator down? If I am gentle acclerating just driving normally I dont here it. When I accelerate harder it makes the noise.
Title: Re: Noise under acceleration
Post by: PenguinGTI on 03 April 2011, 22:56
Right I'll answer the last few together  :smiley:

Penguin, you mention the "whistle of the turbo spooling". I've had several cars with turbos and none of them whistled, I don't think you should be able to hear the turbo from inside the car if it's working correctly, unless you've done a mod to make it audible.
I certainly can't hear it on mine.

The standard turbo whistle cannot be heard from inside the car unless the windows are down. It's the exact same in this respect as the day I got it so no change/worries here.

Does it also make it if:
Your in neutral. You rev the car to ~3K then take your foot off the pedal?


Nope it only occurs under driving load.

Any chance of recording the noise on your phone and uploading it so we can hear it? Would be easier to diganose that way.
I'll assume you don't have any uprated engine mounts or any other mods (dump valve etc)?

Tried this already but it's too quiet a noise for my phone to pic up.  :sad:

Whether I floor it or accelerate gently the noise occurs just before the turbo begins to spool.
Title: Re: Noise under acceleration
Post by: Radek on 04 April 2011, 11:14
I may have had something similar last year. Only under load and only when hot sounded like a whine and with open windows like a nasty diesel. Not the "normal" TSI rattle.
http://www.golfgtiforum.co.uk/index.php?topic=166745.0 (http://www.golfgtiforum.co.uk/index.php?topic=166745.0)

I spoke to 2 dealers, they scanned for codes (that's the only thing they can do) and guess what? It's all ok! They told me - if it goes you have warranty. Brutal but fair.

I think it may be the engines characteristics after all.
Let us know if you find out what that was.
Title: Re: Noise under acceleration
Post by: WILLS on 04 April 2011, 16:54
i get a hissing/metallic rattle between 2  - 3k i've been told this is normal

Mine does the same as this between 2 - 3k and did take it into the garage but they said its normal.

Does it depend on how much you put the accelerator down? If I am gentle acclerating just driving normally I dont here it. When I accelerate harder it makes the noise.

Yep identical to mine  :smiley:
Title: Re: Noise under acceleration
Post by: PenguinGTI on 23 April 2011, 01:45
Finally found the noise I think.

It's not the best quality but here's a youtube clip which has as close a noise as I can find.

http://www.youtube.com/watch?v=7K0GFlLkC0k&feature=related

http://www.youtube.com/watch?v=11lUvQ-XRro&feature=related

From what I've read it's a clutch squeal. One of the guys notices that he only gets it during certain revs (same as me) and only under load (same as me).

The difference is that he replicates the sound with the clutch pedal but I use the accelerator (because my car is a DSG).

I've also gathered that not many people have had it fixed yet so I'm not sure where to go.

I do know that the next service is coming up on my car soon so maybe a change of the DSG oil will help the situation.