Whistling noise at idle

[Fayded33]

Hey guys, i own a  1996 r33 gtst for the past 4 years. It has a 3 inch exhuast and front mount but apart from that is a stock car. Recently i have been hearing a whistle noise coming from the engine (trying to source where it is coming from it sounds like turbo or pod filter) doesnt matter if it is warm or cold it is always there only at idle.

Since it started the car has also began to flutter. Not all the time but if boost isnt fully built up it flutters when letting off the throttle. The bov is stock and has not been blocked off. 

I have checked most hoses for leaks and havent found anything. I am completely lost as to what it could be and cant find any threads that explain this at all.

Thanks for any help.

[KiwiRS4T]

If you suspect your pod filter take it off and see if the noise goes away. How have you checked for leaks? You need to pressurize the system from the turbo to the throttle. Your turbo is 24 years old and could be due for reconditioning or replacement.

[Fayded33]

Turbo has been reconditioned within the past 5 years and i have tested the podfilter, it isnt the issue but that is where the noise is escaping through

[GTSBoy]

You have a vacuum leak somewhere, possibly an exhaust leak. Get yourself a piece of garden hose and go listening. This stuff is not so hard.

[MoMnDadGTR]

19 hours ago, GTSBoy said:

You have a vacuum leak somewhere, possibly an exhaust leak. Get yourself a piece of garden hose and go listening. This stuff is not so hard.

this is definitely where you start. seems like everyone jumps to the big issues before grabbing the garden hose, or a multimeter and actually running some tests for simple issues. theres not that much piping on a gts shouldn't be hard to find the leak m8. and turbo could still easily be bunged after 5 years. ive seen lots of reconditioned turbos bite the dust early.could even be cracked housing on intake side of turbo ive seen this too. do the garden hose test and shout back...

[MoMnDadGTR]

hey mate just wondering if you ever got around to tackling that whistling noise...curious to see what was up