I have a high pitched squeal that sounds like high pressure leaking. When I accelerate, it goes away, when I back off the accelerator it returns. All pulley bearing are good and belt is tight.

Thinking high pressure tranny line? HELP!!!!!

 

Need more info - if it is manual, sounds like a worn clutch.

 

How about a vacuum leak at the back of the intake manifold??????

 

Thanks for the ideas. The tranny is auto. It only begins to squeal when it warms up (As if pressure has built up in ??? and is leaking.) It stops squealing when I accelerate and it returns when I let off the gas. When I stop, it reduces and when I place tranny in park, it goes away.
I've changed every pulley that has a bearing system except the main. I've replaced serpentine belt and tightened to specs.
Had AC system replaced and installed new power steering pump with full bleeding procedures.
Has me beat. Sounds like high pressure from ????