What was found
(CAN) DURING APPROACH ENGINE POWER INCREASED. PILOT COULD NOT CNTL ENGINE WITH THROTTLE CNTL AND CARRIED OUT A MISSED APPROACH. ON A SUBSEQUENT APPROACH AND LANDING, PILOT USED MIXTURE CNTL TO SHUT DOWN ENGINE PRIOR TO TOUCHDOWN. A/C HAD TO BE TOWED FROM RUNWAY. EXAMINATION OF THROTTLE CNTL FOUND THREADED END OF CNTL HAD SEPARATED FROM ROD END WHICH WAS STILL ATTACHED TO CARBURETOR THROTTLE ARM. SUBMITTER SUGGESTS THIS HAPPENED BECAUSE ROTATION OF CNTL KNOB ON THIS CABLE ASSY TRANSMITTED A ROTATIONAL FORCE TO OTHER END OF THE CNTL CABLE WHICH MAY HAVE LOOSENED JAM NUT AND ALLOWED CABLE END TO BACK OUT OF ROD END.