What was found
(CAN) CUSTOMER REPORTED THAT ON GND WHILE TAXIING, THE PILOT LOST THROTTLE INPUT ON LT ENG. SHUTDOWN & RESTARTED AT THE END OF THE RUNWAY & IT WORKED FINE. DURING TROUBLESHOOTING, MECHANIC WAITED FOR AN HOUR TO START THE ENG & ENG RESPONDED WELL. AFTER WARMING UP TO TEMPERATURE & WHEN MOVING CONDITION LEVER TO LOW & BACK TO HIGH & ADVANCED POWER LEVER, THE ENG HAD A VERY SLOW RESPONSE. MFG WILL INVESTIGATE TO ESTABLISH ROOT CAUSE & PROVIDE INFORMATION THROUGH SUBSEQUENT SERVICE DIFFICULTY REVIEW MEETING & SUPPORTING DOCUMENTS OR OTHER AGREED UPON COMMUNICATIONS.