The steering on my girlfriend's 2004 RX-8 is loose; it used to be very responsive, quick to turn. She was making a tight right turn at about 15 mph and caught the curb with her back right tire. At first the steering was only loose for right turns, but after driving it a little, both directions became equally affected. Only the back right tire hit the curb. The car has had an allignment and tire rotation (the one that hit the curb is now on the front right), and the steering is still less responsive to a very obvious degree. On a flat surface, the steering does not pull to either side when accelerating, coasting, or braking; it will drive a straight line without touching the steering wheel. Any thoughts on what is wrong?