Police Siren Noise? Still Boosts Got Vid

[DuFFR32]

Car started making a weird police siren noise a couple of days ago...its easily heared in the video clip i made, what do u guys think? anyone else come across this noise?

[dangerman4]

engine cooling fan maybe.

[DuFFR32]

Def not the cooling fan the sound is coming from the turbo side of the engine ahh looks like i will have to pull the piping off and sheck the compresser side of the turbo for play. not a bad movie for a 1.3mp phone mounted in the hole of the headrest

[limpus]

Had the same sound when i did my 2535 install on my old 32 years ago...checked everything and couldn't find the cause of it...funnily enough...adding a resonator along the catback to reduce exhaust noise levels totally got rid of the siren wailing sound too...i put it down to some sort of weird resonant frequency which was eliminated with the addition of the resonator...now its highly possible its totally unrelated but i spent 6 months hunting down the cause so regardless i was happy...

[geraus]

sounds like a boost leak? check your cooler pipings

[R31Nismoid]

could have told us @ what point it started in the video - as opposed to waiting 2mins!

one of 3 things

boost leak/slight break in seal somewhere along the hosing

clutch fan

dying turbo

[DuFFR32]

Found problem!!! Broken 2 bolts off dump of turbo underneath broken due to rapid heating cooling of that area of turbo I guess...and oh found a broken manifold stud as well at the back so hopefully fixing that will fix the whail sound.

You can hear the sound in the vid heaps of times all the way through its the noise like a whail sound as the turbo spools up. Will make another vid to better show the noise

Thanks for the input guys

Very happy skyline owner!

[R31Nismoid]

re: manifold stud - make sure you change ALL of them at the same time