As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT ENGINE VIBRATIONS. *S/D* VIBRATION WAS NOT CONFIRMED BY ENGINE CONDITION MONITORING. GROUND RUN VIBRATION SURVEY WAS WELL WITHIN LIMITS. BORESCOPE INSPECTION REVEALED NOTHING ABNORMAL. LUBRICATED THE FAN BLADE ROOTS AND RERAN THE VIBRATION SURVEY. ALL STILL WELL WITHIN LIMITS. REPLACED VIBRATION ACCELEROMETER, PRECAUTIONARY.