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Hey guys,

I have a 95 Gtst 5spd and when driving there is a high pitch squeel coming from the motor.

Now at first i though it may of been the turbo, so i bought another one yesterday (had very very little shaft play in and out, none up and down)

and fitted it but...i still have the sound. The sound only comes when i am high up in the revs on full boost (about 8psi, thats what the guage says)

So first and Second gear mainly at about 4500-5000rpm and then upwards from there .... but not when i am in 5th gear foot flat at full boost

Would it be possible the BOV is leaking and making the sound? When revving the car from under the bonnet and looking at the BOV it seems to open slightly when it hits the little bit of boost

The only Mods to the car is a full 3" system, HYBRID FMIC, GFB BOV TYPE 1 i believe, GFB Atomic Boost controller, and a boost guage

any help would be appriciated

Tim

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https://www.sau.com.au/forums/topic/306317-strange-engine-noise/
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Sounds like a leak, why don't you try blocking it off?

If that doesn't work, tighten all the hose clamps on the pressure side and try again, leaks can make all sorts of weird noises especially as you go higher up in boost.

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