S60 T5 strange sound

[Serdar-S60T5]

hi everyone.
last night i noticed a strange sound coming from outside the cockpit right after i pulled my foot off the gas pedal.
i stopped and tried again. from a standing start, dtsc on, i gave it half throttle, got it up to around 4000-4500 revs and then suddenly let it off without touching the brakes or anything, and right after i let it off, i hear a loud and strange echoing wooooshh.
i suspected the turbo hoses but the car is still pulling as good as it was before. so i'm guessing it shouldn't be a boost leak, but i'm not sure. what do you think?......

[Mrsmopp]

I think it might be your recirculating dump valve tbh depending on what your "whoosh" sounds like!

x

[Serdar-S60T5]

I think it might be your recirculating dump valve tbh depending on what your "whoosh" sounds like!
x

thanks mate...
just been to the service and the guys over there have no idea where this sound is coming from. they checked the hoses and stuff and all seem ok. there are no error codes or anything either. we also went for a test drive and the car is pulling like it always does.
do you think i should change the dump valve anyway?
what would happen if it really is the dump valve, but i keep driving it like this?

[Mrsmopp]

If it is thet recirc then its nothing to worry about, they all do this So no need to change the DV, no need to worry and keep driving it as normal.

Is it like a forced air noise after you have booted it and then let off quite hard?

x

[Serdar-S60T5]

If it is thet recirc then its nothing to worry about, they all do this So no need to change the DV, no need to worry and keep driving it as normal.
Is it like a forced air noise after you have booted it and then let off quite hard?
x

actually now that i've listened to it more and more, it sounds more like a "khoooshh" rather than a "woooshh". and it becomes more obvious and loud if i let off around 3000 revs where the turbo is just kicking in - but can't really totally kick in because i'm suddenly letting off...
it is like some valve closing and some forced air noise.

[bubba_1986]

actually now that i've listened to it more and more, it sounds more like a "khoooshh" rather than a "woooshh". and it becomes more obvious and loud if i let off around 3000 revs where the turbo is just kicking in - but can't really totally kick in because i'm suddenly letting off...
it is like some valve closing and some forced air noise.

Def sounds like the recirc valve, note: this is your dump valve, just doen't dump the air to atmosphere.

Instead it recirulates, this is how the noise you hear is diffrent from a normal dv

[Rufe]

have you been driving around with the passenger side window open... its a bit more noticeable when the passenger side window is down

[Serdar-S60T5]

have you been driving around with the passenger side window open... its a bit more noticeable when the passenger side window is down

definitely mate !!
the sound is coming more from the front right side of the car annd i'm hearing it more clearly when the passanger window is down.