Whining sound under boost.

[Gunnar]

Rebuilt engine, new 57 trim turbo, 2000km old original hks SSQV.
When i start boosting i hear a whining noise coming from the engine, it sounds somewhere between a supercharger whine and a starwars spaceship :-)

It didnt do it after the rebuild, just a few weeks later.

I checked for the obvious things like boostleaks with a boostleak tester, checked manifold for leaks. Could it be the SSQV? When testing for boostleak it didnt blow.


Edit: and yes i chekcked shaftplay on the turbo, it is still like new, no touching anything on the sides etc.

[Mk3runner]

deathwhine?

[s383mmber1]

What does your oil feed line look going to your turbo?

[KicknAsphlt]

I had that whine, ended up being the turbo to manifold gasket....it had delaminated and a couple of the mounting nuts on the turbo had worked loose...so air was blowing by that gasket and vibrating the layers.


Rebuilt engine, new 57 trim turbo, 2000km old original hks SSQV.
When i start boosting i hear a whining noise coming from the engine, it sounds somewhere between a supercharger whine and a starwars spaceship :-)

It didnt do it after the rebuild, just a few weeks later.

I checked for the obvious things like boostleaks with a boostleak tester, checked manifold for leaks. Could it be the SSQV? When testing for boostleak it didnt blow.


Edit: and yes i chekcked shaftplay on the turbo, it is still like new, no touching anything on the sides etc.

[CajunKenny]

Could be a belt.

[black91turbo]

Check all of your intercooler couplers....

[thevork]

i had that some time ago. turned out to be a coupler that wasn't tightned down enough and air passing the gap would cause a whistle.

check your piping ;)

edit:
i didn't see that black91turbo said the same thing. sorry my bad.

[Gunnar]

I did pressurize the system way over the normal boostlevels nothing popped off or blew air.
That turbo gasket seems like the next thing to look for.

thanks for that suggestion.

[CajunKenny]

Did you leave it pressurized for any length of time watching for a pressure drop?

[Pandaplastic]

I did pressurize the system way over the normal boostlevels nothing popped off or blew air.
That turbo gasket seems like the next thing to look for.

thanks for that suggestion.
Get a Spray Bottle and some soapy water. Spray the piss out of the couplings. If bubbles start forming you have a leak. 20psi is good for the test.

[IJ.]

Mk3 owner it's just your wallet :)

[Gunnar]

:-)

I just call the car stuborn that's all.