howling noise at higher revs..

[darko]

sadly not a nice one... this has been happening for a while and i thought it was the exhaust but now having spent more time tracking it down i think it may be coming from the engine bay. the sound is like blowing over the top of a milk bottle and happens just after 4K. i can sometimes make it happen while not under load but very rarely, is it the death yelp of the turbo dying ? has anyone else had this ? the car is running fine, in fact has never been better but this noise certainly isnt right !

 

[icenutter]

Check the air hoses under the bonnet for leaks; particularly around the air-box.

 

[JamS3]

Sounds defo like a air leak poss in the intercooler pipes...

 

[darko]

yes, i think it must be - ill have to work my way around them or i guess take it to a rolling road to stand a beetr chance of finding it. im just hoping its not the turbo..

 

[JamS3]

The right pipe is fairly easy to take off for a look, the left one is a bas*tard!

Put it on ramp and the ones underneath the car can be easily examined

 

[s3bow]

Try looking at the small u-shaped pipe on the LH side of the inlet manifold (as you look at the engine). It splits on the inside of the U. Have a real good look as its not immediately apparent. It splits right on the inner seam. It is attached to another pipe by a rubber block. Just cut it off with a blade and replace it with a small Samco 135deg bend. I had the front bumper off and everything stripped trying to find a boost leak. Turned out to be this.

Are you sure its not just the sound of the turbo working harder ? Is it mapped ?

Chris.

 

[Paul-RS6]

knackered DV (ie air passing over a split diaphragm) can cause this noise.

OEM one will cost you about £15.

 

[s3tle]

hello
did you ever get to the bottom of this? think mine is starting to make a similar noise

 

[jamiekip]

I had the timing belt and clutch changed on my S3 requiring most of the turbo hoses to be removed, as soon as I took the car out, by the time 3k of revs was shown, the boost was blowing air everywhere. So definately check your hoses, mine turned out to be the intercooler hoses so had to go back on the ramp to be checked. If you can get it on a ramp it won't take to long to find out if it's a lean from a hose coming loose, or whther its from a hose splitting.