As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENGINE FAN "LEFT" VIB 2.9 AT FL330 RAN QRH VIB DID NOT DECREASE BELOW 1.8 UNTIL AT FL250 WITH REDUCED THRUST / REMOVED BLADE PINS IN LH ENG DUE TO HIGH VIBES. REPLACED LH ENG BLADE RETAINING PINS IAW CRJ 900 AMM 72-21-02-000/400-801-A01-PSA. PERFORMED LH ENGINE VIBE RUN IAW CRJ900 AMM 71-00-00-720-806. OPS. CHECK GOOD AT THIS TIME