What was found
LEFT ENGINE ENGINE COMPRESSOR STALL: AFTER BEING IN CRUZ FOR AN HOUR AND A HALF DURING INITIAL REDUCTION OF THE THRUST LEVERS, THE AIRCRAFT SHUTTERED/THUMPED FROM THE REAR OF THE AIRPLANE LIKE THE BOV STUCK. HEARD NOISE AND FELT A LITTLE KICK IN THE RUTTER PEDALS THINK IT WOULD BE THE LEFT ENGINE. ALL OTHER ENGINE INDICATIONS WERE GOOD, EXCEPT NOTICED A LITTLE FLUTTER IN THE LEFT ENGINE. THIS HAPPENED AT 43000 FEET. REMOVED AND REPLACED TQ MOTOR. P/N OFF-ON 30J4133-01 S/N OFF TRAXY000987,, S/N ON TRAXY000616.