"Clanking" noise on left only turns
 

I own a 2005 Hyundai Tiburon with 15k. I am hearing a "clanking" sound on
slow speed left only turns. This noise occurs when the wheel is 1/3 - 1/4 the
way cocked left and happens in both drive and reverse. The noise is sporadic
and doesn't seem to pattern temperature, moisture, etc... It is under
warranty and the dealership has given up. Their best explanation it that
thereis an "over-turn stopper" that is rubbing due to me over-turning. This
can be the case since I'm exhibiting this noise at non-full left turn and
nothing on right turns. Any ideas what to do next?

-Craig