As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RETURNED TO DEPARTURE, DUE TO HIGH N1 FAN VIBRATION 2.8 IN CLIMB POWER SET ITT AND N1 NORMAL. INSPECTED NR 2 ENGINE INLET FAN BLADES, EXHAUST AND CHIP DETECTORS. NO DEFECTS FOUND. GROUND RAN ENGINE VIBRATION .8 MILS WITHIN LIMITS REF CF34 ENG MANUAL 72-00-00, TESTING 01 PAGE 1325 AND 1326. (M)