As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ENROUTE THE CREW ELECTED TO RETURN TO POINT OF DEPARTURE DUE TO A SUSPECTED ENGINE VIBRATION. AFTER ARRIVING, THE MAINTENANCE PERSONNEL INITIALLY REPLACED THE FORWARD ENGINE MOUNT ISOLATORS WITH NO APPARENT REMEDY OF THE PROBLEM. THE FCU WAS REPLACED AND THE ENGINE RUN UP WITH NO FURTHER VIBRATION INDICATION.THE AIRCRAFT WAS RETURNED TO SERVICE WITH NO FURTHER PROBLEMS. (TC NR 20060725002)