George, that car has been there a long time! Your descriptions don't make sense. The screeching you here sounds like a belt slipping. Your description of it seems backwords as the screeching is usually a loose belt and a strong resistance from the AC drive pulley. If in fact your system is losing pressure there would be little pressure. Beyond that, if you don't care about having AC simply remove the feed to the side of the compressor, like this the pulley just spins. Of course the noise could be coming from another belt pulley!
