I've replaced the regulator in both driver and passenger windows about a year ago on my '99 Grand Sport. A few months ago I noticed a loud high pitch noise that I thought was coming from the door switch panel. When the button is pushed down the noise starts immediately. Release the button and try again and the window opens at normal speed. I'm pretty sure the noise occurs randomly on the second attempt and stops in about a second while the window is going down.

I went to the junkyard, got a new switch panel from a '99 Grand, installed and it worked like a charm. Few days later, I'm opening the driver’s window and the weird noise comes back - sounds like its coming from the switch. So obviously the same problem with two different switches suggests it something else. What is puzzling is that after listening to this for a few months, I'm convinced the noise is coming from the switch when I'm assuming it should be the regulator? Any suggestions are appreciated.

 

Try using dry lube or silicone spray on the window channels, and try rolling the window up and down.