1. THE VEHICLE WAS PARKED ALL DAY OUTDOORS ON A HOT SUNNY JULY DAY IN TEMECULA, CA. WHILE DRIVING IT HOME ON I15 AT APPROXIMATELY 70 MPH, THE STEERING WHEEL BECAME MUCH MORE DIFFICULT TO TURN AND WOULD NOT STAY ON CENTER, MAKING IT CHALLENGING TO SIMPLY STAY WITHIN MY LANE. THIS LASTED FOR 10-15 MINUTES, THEN THE STEERING RETURNED TO NORMAL. FORTUNATELY, THIS SECTION OF FREEWAY IS RELATIVELY STRAIGHT AND THE TRAFFIC HAPPENED TO BE MODERATE. 2. THIS FAILURE HAS OCCURRED ONLY ONCE IN THE 6 WEEKS I HAVE OWNED THE VEHICLE. 3. I HAVE NOT YET TAKEN STEPS TO CORRECT THE FAILURE. HOWEVER, I HAVE SEARCHED ONLINE FOR STEERING ISSUES WITH THIS YEAR, MAKE AND MODEL AND LEARNED THAT MANY OTHER OWNERS HAVE EXPERIENCED EXACTLY THE SAME ISSUE. THOSE WHO HAVE ATTEMPTED TO HAVE THE ISSUE CORRECTED BY THEIR LOCAL DEALERSHIP SAY THE REPAIR REPORTEDLY INVOLVES REPLACING THE ENTIRE STEERING COLUMN AT A COST OF NEARLY $4000. MY VEHICLE HAS UNDER 20,000 MILES BUT IS BEYOND THE 48 MONTH WARRANTY PERIOD. HAVING READ RECENTLY IN THE NEWSPAPER THAT NHTSA IS INVESTIGATING POWER STEERING ISSUES IN 2003-2005 BMW Z4'S, I AM TRYING TO FIND OUT IF THERE IS A KNOWN SOLUTION TO THIS PROBLEM THAT IS LESS COSTLY OR THAT IS COVERED BY THE MANUFACTURER BEFORE COMMITTING TO A $4000 REPAIR ON A LOW-MILEAGE USED VEHICLE THAT I ONLY RECENTLY PURCHASED. *TR