Theres a squealing noise with the AC on when I rev the car at idle. The noise gets really bad when I try to make a turn too. It noise goes away when the AC is off. What exactly could it be? Crank pulley, AC clutch ?? TIA

Most squealing noise is NORMALLY the belt, try some belt dressing, and see what happens. I had the same problem, it only squealed when the ac was on. It didnt make any sense, but the dressing make it go away.

Could be the belt, but in my experience, the extra strain from the a/c really makes a separated crank pulley go nuts...... check the pulley ASAP.

yeah ziptied is right; I'd check the crank pulley, they've been known to fall apart on toyotas

thanks for the info guys!

other than the possibilities from above, could it be the AC pump?

not the pump, no. Could be the clutch. but doubtful.

i took it to a mechanic and he said it was the ac pump, but i dun know if i should trust him.
I tired using some belt dressing but it didnt work. The noise is pretty bad at a certain low rpm, like when I make a you turn at low speed, the noise is really loud.
so it could be the clutch or crank pulley?

Well, ill put it to you like this. When I had my MKIV TT Supra, it made a really bad squealing noise, I took it to my local toyota dealer, who said, it was my ac pump. I got home, took the belt off and the crank pulley came apart in my hands...... replaced it and it never squealed again.

damit! i have the exact same problem and i just replaced my t-belt and crank pulley, the oem used crank pulley that i bought looked to be in good shape when i put it on, but i guess not? i will check tomorrow