As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 2 ENGINE HAS HAD A SUDDEN INCREASE OF FAN VIBRATION LEVELS. ACFT GROUNDED. CHECKED INLET AND EXHAUST REF AMM 71-00-00-800-802. NO DEFECTS NOTED. ACCOMPLISHED FAN BLADE LUBE REF T/C 78478002. REPLACED THE NR 11 PLATFORM DUE TO MISSING RUBBER SEAL. NO OTHER DEFECTS NOTED. ACCOMPLISHED POWER RUN/ VIBRATION SURVEY REF AMM 71-00-0--700-814-F00. ALL VIBRATIONS WITHIN LIMITS.