I have a 87 300zx and have problem with the driver side window. It is in the up position, it won't go down. I can hear the motor clicking like it is trying to work and if I hold down the switch for a few seconds it will break a relay. After a few seconds the breaker will reset. I took the door panel off and inside the door at the bottom I found a metal and plastic piece about 1 inch in diameter. The metal piece has threads thru it. Could that have anything to do with my problem or is it left over from a previous broken window.