Chirp and Squeak Under the Hood!!!

Hello all,

My wife has a 2001 Mustang V6 (80k miles). There is a loud chirping and squeak noise coming from the front of the motor.

I have replaced the belt, water pump, idel pulley, and tensioner pulley. None of these have fixed the problem.

Then I started to look at the Cam sensor and wondered if it was rubbing but do not see any evidence of this.

It seems like when the car really starts to chirp the rpms vary some.

What could be generating this sound? Sounds like it might be coming from the harmonic balancer, or general area.

Any help will be greatly appreciated!!!

Update:

I did a test and ran the vehicle without the belt for 10 secs. The chirping and squeaking is still there. I don't see anything physically wrong with the harmonic balancer ( at least externally )

I have read posts about the Camshaft Position Sensor unit bearings going out. Is this possible?

A few more facts. I didn't hear this noise until after the oil was changed in the vehicle.

There is oil in the vehicle, it is the same weight as always, it has never lost oil pressure.

Michael