If your ignition lock cylinder wont return to the run position after you turn it to start, then your ignition rack gears are most likely stripped out. The gear is plastic and wears over time which in turn, will not be able to actuate the ignition switch when you turn the key to the start position.
This kit comes with:
A 6 tooth gear(5 small teeth, 1 large tooth)
Metal ignition rack
Return spring and mounting screw
Fits Cadillac automobiles 1977-1995 with tilt steering wheel