got a 98 civic with 200,000 miles, the ac blows fine and the air is cold but when u turn the ac on the car makes a loud shreeling noise, the noise might last 30 secs or just a few seconds, but it is so loud i'm ashamed to leave it on for too long..but when you turn the ac off, the noise goes away immediately, and the car never has made the noise unless the ac was on....any ideas guys, i have no idea where to start!