Have you tried making sure that the exit adjustment lever still works on the left side of the steering column. When I first got my svx, it took me a day to figure out the height adjustment is actually on the bottom of the column and the lever on the side is just used to push the steering wheel out of your way when getting in and out, and only locks in the full up position, and then returning to the position you set for the height. check that, and if it won't hold, maybe something has gotten stuck between the latching mechanism and the gear tooth.