[pysical]

Specs:
Speedtech bottom mount 6466
PR Intake 1050cc injectors
VTT valve cover/catch cans
B58 coils
new plugs

Last year I restored my car from an accident. I was taking it easy the first couple of weeks and slowly going back into boost little by little. One day I took it out for a drive with the air filter off. Was just doing a little test. Anyways I did a mini pull and then in the middle of it the boost just let all out completely. I thought that was strange and did it again. After that, the turbo started to make a whine/siren noise. So I brought it home.

I had a look around and nothing out of the ordinary. My guess was that maybe the inlet collapsed? Its a speed tech bottom mount and its a pretty large inlet.

Anyways, I decided to swap the turbo out with a brand new one. Noise is still there. Then I put my original one back on since I had Precision rebuild it and the noise is still there.


It happens while in vacuum and goes into boost. It does need load though to get it to happen. I have tried a boost leak test and everything was good. I did a smoke test and couldn't find anything but might give it another shot.

Hopefully someone has an idea?

This video is taken with my phone on top of the engine while driving.
https://drive.google.com/open?id=1YN...Q3P0zNDVclZv97

[ReForMatt]

The video didn't play when I clicked the link but ...maybe modify a oil cap with a vacuum gage with a line long enough to see it. Or maybe explain your catch can configuration. I had the issue but could hear it during idling removed the oil cap an could feel excessive vacuum putting my hand over the opening, adjusted my vacuum relief spring no more issues. Hope this helps narrow down some trouble shooting. Good luck 👍

[pysical]

Originally Posted by ReForMatt

The video didn't play when I clicked the link but ...maybe modify a oil cap with a vacuum gage with a line long enough to see it. Or maybe explain your catch can configuration. I had the issue but could hear it during idling removed the oil cap an could feel excessive vacuum putting my hand over the opening, adjusted my vacuum relief spring no more issues. Hope this helps narrow down some trouble shooting. Good luck 👍

My catch can configuration is the VTT dual catch can setup with the VTT manifold. One goes to the TB and the other is VTA.

I can kinda hear a similar noise while at about 1k rpm at idle. It sounds like it is coming from on top of the valve cover in the back. I tried unplugging the banjo fittings that go to the valve cover for the catch cans and it was still there.