Have a 2003 G35 sedan, with about 131,000 miles, everytime I roll my window up (pushing the button all the way so that it automatically goes up) the window will close and than immediately open about 6 inches..with out me even touching it...its weird, and now all of a sudden my passenger window is doing it too. The only way i can close them is if i leave my finger on the button the entire time...anyone know anything about this or ever run into this? Thanks.

 

You can reset the window travel. Search for the procedure on the forum. The ultimate cause though is a failing motor. You can try the reset procedure, but if it does it again you will need tp replace the window motor.

Edit: http://www.infinitihelp.com/diy/gcou..._procedure.htm