What was found
(CAN) DURING GROUND RUN AFTER PERFORMING A FUEL NOZZLE REPLACEMENT, LT ENGINE WAS SET TO TAKEOFF POWER AND PARAMETERS WERE COLLECTED. AFTER REDUCING THE ENGINE NR 1 POWER WHILE IN PREPARATION TO INCREASE POWER ON ENGINE NR 2, THE TECH HEARD A LOUD BANG AND NOTICED THE ENGINE NR 1 LOOSING SPEED AND ITT DROPPING. THEY SHUTDOWN AND SECURED THE ENGINE NR 1. A BOROSCOPE INSPECTION WAS CONDUCTED AND NO DAMAGE WAS FOUND ON THE HP AND LP SECTIONS. THE ENGINE WILL BE SENT TO MFG FOR INVESTIGATION AND REPAIR.