Belt squeal... with no belts???
 

So I thought I was getting high rpm belt squeal and I bought new belts and put em on even though the old ones looked perfect but sadly the noise was still there.

-It sounds exactly like belt squeal except maybe a little quieter.
-It only happens from 5200-7000 at 70%-100% throttle

So here is the crazy part, after going completely insane trying to identify the source I took both belts off to do a sanity check and REAL fast buzzed up a couple times and it was still there. NO BELTS BUT STILL SQUEALING
After putting the belts back and being more confused then a 6year old in a sex shop i popped my intake tube off at the air filter side (running ms on otherwise stock 1.8 protege motor).

With the intake open you can hear it more and it indeed sounds similar to belt squeal, but it's probably a whistle
Car runs perfect and real strong..

Im guessing maybe it's a gasket or something poking into the airflow making like a whistling noise??? I don't know though and when boost happens (veery close) I'm sure I won't hear it at all...

Any ideas? ---- it, let it whistle?
It's been doing it for like 3000 miles that I've noticed, and its not very loud with the intake together. It doesn't sound harmful either if you know what I mean.

Thanks team

Bearing issue? Idler maybe?

Yeah maybe one of the timing belt pulleys?

Or you have a vac leak, either one of the barbs is open, or the intake manifold may not be on tight enough, and it creates a whistle at those RPM's. Usually this will create idle issues as well though.

Well I did a timing belt job about 5000 ago with new idlers, waterpump, and belt so Hopefully its not that. If it is that then ----, I'll find out when it breaks.
Lol gonna start carrying a spare tb kit around with me

As far as like a vacuum leak, I idle at around 27-28 kpa..
Maybe I should just start plugging stuff off. If that doesn't do it then maybe I'll pull the intake and take a peek around. When I swapped the motor in 5000 ago I had to chase down a few vac leaks which ended up being at the injectors. I guess I ought to double check everything.

It's possible I blew the welds on the intake though...

Listening to it more tonight it sounds like a whistle a whole lot. You can't hear it with the windows up either but the way it starts and stops is exactly like belt slippage to give you peeps more of an idea.

Thanks for the help 2ndGear and Mobius

Another thing too, it SEEMS as far as I can tell, to still run perfect on the stock computer. My wideband agrees as well