Loud boost leak sound

[woody.dub]

Hi,

for weeks now i have had this loud hissing sound when on boost. I know your all thinking boost leak.
I have presure tested the whole system found my 007p leaks above 8psi but thats it. so looked at the intake pipe, I have removed the PCV return from the TIP and blocked this off the noise still there.
removed the DV completely used bungs both sides, still the sound is there.

Im running stock air box, it does it with both BMC filter and stock.

Any help would be great?

thanks

Woody

 

[sportstractor]

maybe the tip is split?

 

[woody.dub]

changed that too

 

[DJ_Troopa]

Where is the noise coming from? Which area of the engine bay?

 

[woody.dub]

from in the car it sounds like its coming from behind the glovebox if that makes sence

 

[g10chy]

My car does this...As far as im aware its completly normal and got louder after putting a green cotton filter and 007p on.

 

[DJ_Troopa]

My car never made this noise when i first bought it and it had a standard airbox. Green cotton panel filter made it a bit louder though.

 

[woody.dub]

no i dont think its normal i have been in other S3's and TT's etc that dont do it

 

[coyle]

mine does it, its alot more noticeable since fitting my jetex and forge split R,
sounds like its hissing out air under acceleration? that the same noise?

 

[woody.dub]

yes thats the noise a loud hiss just like a leak but my block 032 readings arnt bad at all

 

[s3gazz]

my car does this 2 hissing noise when on boost one day it was quite next hissing on boost iv got newspeed and split r thourght it was turbo like ha

 

[woody.dub]

its horrid i really dont like it

 

[coyle]

im not sure why it does it, i need to get a boost gauge in to see how it acts on boost.
but it feels fine

 

[finesse]

I have this too but only in 4th gear +

 

[rossbrownlee]

not that i am doubting your pressure test mate but did you have the bumper off and test the flanges at the top and bottom collectors of the intercoolers? Mine burst here right at the top of the nearside intercooler at the flange between the finned cooler section and the top plastic collector section.

 

[s3dave]

Its possibly the turbo spooling?...mine is very loud, sounds like a shhhhhh sound

 

[Welly]

Behind the glove box is the turbo/tip sort of area...

Have you checked the turbo outlet pipe from the turbo to the charge pipe for starters.

Failing that, and you are sure there are no leaks, check the actuator pipe for splits.

 

[s3dave]

Behind the glove box is the turbo/tip sort of area...

Have you checked the turbo outlet pipe from the turbo to the charge pipe for starters.

Failing that, and you are sure there are no leaks, check the actuator pipe for splits.

yeah good shout, with the turbo outlet to charge pipe being an orangey colour if it is leaking you will be able to see or feel for slight greasiness, like oil vapour

 

[Lloyd149]

Try meet up with someone on here, see if their S3's have the same sound your experiencing. As said before, now i've got a Forge TIP, DV and panel filter, mines making more of the swooshing sound on spool up.

Recently replaced my TIP, and found the original, at the turbo end. The jubilee clip was properly loose.

 

[Welly]

yes thats the noise a loud hiss just like a leak but my block 032 readings arnt bad at all

What engine is it? And how bad is not bad?

 

[s3-oz]

I have this loud hissing noise too and interested to know what it is!!

 

[marrick92]

I also have a loud hissing on acceleration, thought it was a boost leak but on my VCDS the MAF is showing bang on 10 g/s at 3000rpm??