2002 BMW Z4 Power Train Problems

BUT BOUGHT WITH LESS THAN 12,500 MILES, THEY FOUND TURNED UNSTABLE SITUATION, HAS BEEN UNABLE TO FIND WHAT THE REASON, AT TIMES ALMOST A MAJOR ACCIDENT WHEN DRIVING, THE TIRE DOES NOT FEEL STICKY, BUT ON THE HIGHWAY, THE CAR IS ALL OVER THE PLACE (LIKE A DRUNK DRIVER), THE STEERING FEELS VERY LOOSE, NOT TOO SENSITIVE. IF I DO ANYTHING MORE THAN A SLIGHT ROTATION, DYNAMIC STABILITY CONTROL SYSTEM HAS BEEN STARTED, IF THE CURVE WENT TO THE RIGHT, I HAD TO "JERK" TO GO STRAIGHT TO RECTIFY THE SAME, IF IT WENT. WHEN A STRAIGHT ROAD, IT WILL FEEL VERY STICKY, MOVING WHEELS. THIS IS VERY SCARY, BECAUSE IT CAN NOT BE DIVERTED AT ANY TIME, I WILL LEAVE THE ROAD AND DOWN MILES OF CANYON CREEK. THIS SITUATION WILL NOT OCCUR AT LOW SPEEDS. UNFORTUNATELY, I HAVE A LOT OF PROBLEMS WITH MY 2003 BMW Z4 STEERING...