I have this problem with my 2001 Monte Carlo, this is the real deal......the gasket in the widow trim expands and prevents the window from going down. Apparently the motor does not have enough torque when this happens.

The time it happens is when the whether gets hot. In the morning when it is cool....38-45 degrees.....it will come down. No kidding, this happens to me all the time.....both sides of the car.

I try to remember to crack the window on hot days.

Ron

 

yah this happened to me it was some rubber piece behind the plastic my window actually came off track to and about fell out.

 

Just to update, I never fixed the window due to the cold weather up here. Either way I was driving to work this morning and accidentially hit the passenger side window and it works again perfectly!!! What the hell could this be?