As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK DUE TO CLIMBING THROUGH FL 330, NR 2 ENG ROLLED BACK TO 65 PERCENT N1 FOR 30 SECONDS. DESCENT WAS STARTED AND ENGINE RETURNED TO NORMAL OPERATION. PMC CYCLED OFF WITH NO CHANGE IN ENGINE OPERATION. REMOVED AND REPLACED NR 2 ENGINE MEC AND PUMP ASSY PER BOEING MM. LEAK CK GOOD. PERFORMED HIGH PWR RUN, PARAMETERS CK GOOD ON GROUND (LPG 75819).