Strange noise when spooling up?

[98gst14b]

I have a gst with a e3gt. Recently I have been hearing a strange whistling, whining noise whenever I spool up very similar to an alternator interference with a stereo. I checked the turbo and its perfect no play at all. Could it be a boost leak and air is whistling out? Thanks for your help.

 

[ROOKIE1]

I would say boost leak . One way to find out .

 

[98gst14b]

Boost leak test in the mornin

 

[yellowrs]

Check where the intake manifold meets the head

 

[cumpersgsx]

i would say looking at your profile since you have a fmic look at all the piping, check the tb elbow to tb. Check by the injectors since those are upgraded...look around anything that has been upgraded.

 

[oldman]

.look around

No look arounds allowed, real boost leak test only!!!!!

 

[98gst14b]

No boost leaks

 

[ROOKIE1]

Compressor or pump ? What pressure and how long did it hold ? Engine hot or cold for test ? Was the engine at 30* past TDC ? Did you listen or did you use spray bottle with soapy water ? Listening does'nt count .

 

[98gst14b]

Used a plumbers cap with a tire valve, pumped to 20 psi with bike pump. Engine was hot, air was leaking out mbc weep hole, held over that and watched pressure, dropped extremely slow if at all. Tried tightening the bov a little and sound still persists. It honestly sounds like death whine from a shot turbo but I checked play again and perfect. I might add recently it has been kinda cold (about 50-60 deg) could the air density make this sound?

 

[98gst14b]

thoughts?

 

[twocanewayne]

Man mine has starter the same thing now that it has got cool out. No leak either, I need to see what folks say also.

 

[crazy_quick]

check for cracks in your exhaust manifold. also check the exhaust gasket between many and head to see is it is bad.