2003 grand am gt-My passenger rear window falls down and will not go up with regulator. The motor & regulator are working. It will go down under power but not up. There was a small white piece (broken) in the bottom of the door. I don't see where it would go or what it does. Does anyone have a diagram showing the parts of the window/regulator assembly?

rock auto has pics of the regulator, the white thing is likely part of the regulator that holds the cable end. they get brittle and break

Thanks! I'll check it out.