As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTS THAT THEY RETURNED TO DEPARTURE ON ACCOUNT OF THE NR 2 ENGINE VIBRATION. THE AIRCRAFT WAS GROUNDED. REMOVED AND REPLACED THE NR 2 ENGINE BPRV. PERFORMED A LEAK TEST OF THE BLEED PRESSURE REGULATOR VALVE IAW AMM 36-11-52. NO LEAKS FOUND.