Basically the design of the tilt in the star/quest relies on a threaded rod that is rotated when pulled by the rod attached to the T-handle under the steering wheel. Essentially it is a "bolt" and nut, with the nut welded to one side of the clamping mechanism. The problem comes when the "bolt" gets a little stretched and can no longer clamp the slider part of the bracket that allows the column to move up and down.
To fix mine, I made a shim to fit up in the clamping section so the slight rotation of the bolt clamps down firmly on the slider. Those of you who have had the pleasure

I cut a small rectangle of some sheet metal aproximately .020" thick(the thickness of your shim may vary depending how loose the clamping mechanism is) and the approximate rectangular shape the clamping mechanism(about 3/4" by 1.5") and drilled a hole in the center of the rectangle. By the way, if you want to know the exact thickness of the shim needed, use a feeler gauge and stick various thickness gauges in until you find the one clamps down with the T-handle the best. The diameter of the hole in the shim is slightly larger than the "bolt" diameter. However, since you cannot remove the "bolt" you need to notch the drilled hole out to one of the long sides of the rectangle to allow the shim to be slipped into the clamping slider(it will look like a bumper shim when finished except more of rectangular shape). Just make sure you slid the shim in from the top so it doesn't fall out when you loosen the slider to adjust the column.
Sorry my explaination sounds pretty complicated but its really a pretty easy fix.
I used this method several years ago and my steering column works as good as new.
If you want to do it this way and need help, let me know I could quickly explain it with a phone call.
Hope this helps,
Dave