Its the window regulator motor. Exact same thing happened to my 98 rolla and i replaced the motor on the window regulator and it works like a charm now. Its pretty easy to replace yourself. Just go to a junkyard and get a new regulator and replace the whole assembly. Take the door panel off, and then take the little plastic clips holding the window to the regulator off, take the window out, unbolt the window regulator, then just manuver the regulator out of the door frame. *You will have to open and close the regulator in order to be able to get it out of the frame*