Thread: Screeching sound, but not from belt

Internal, you don't want to go there.

Might be a bad balancer, typically not a screech, but can be. Since you pulled the belt, that gets many other things out of the way. Might be a PCV malfuntioning.

I pulled and inspected the PCV... it's clean and working fine. There is no excessive internal vacuum or back pressure.
If I punch the throttle I can get a quick screech (just like a belt would make).
If I slowly increase throttle, it will run smooth until about 3500-4000rpm before it starts to sound off... and all this happens with the belt off???