I recently purchased a used 2004.....the passenger seat tilt back/forward mechanism never functioned well i.e. sticking, clunky, etc. This weekend something broke...... the back will go completely forward and total back,,,,, but we lost all the intermediate stops......

Can someone give me an idea as to what needs replaced......????? I took off the lift lever, but have not dug any deeper yet......Any ideas.
thanks
C