120K miles and 2001 model, when it warms up, the squealing sound goes away

Its probably the alternator belt.it needs tightening or replacing!

You have a loose belt.

your belts need to be adjusted.

It Is Brake oil. It is pretty old car .So go to the Infiniti service Center.The screw is pretty lose so try not to do your self because l had my ml320 Benz 2001. l went to service center the fix it up so l do not have squealing sound anymore.

the mouse does not want to be woken up.

Check the all of the engine belts for correct installation and tightness.

Loose belts is generally the reason most cars make a squealing sound upon start-up. My father drives a 2001 Subaru Outback and it used to make this same squealing sound upon start-up. However, after tightening the alternator belt, the squealing stopped.

It is the serpentine timing belt, have a dealer replace it. Do not attempt to fix it yourself. They should also check the main pulley for possible wear/replacement.