As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEVELING OFF AT FL370, E1 LPVIB IND 4.0, REDUCED THROTTLE AND IT REDUCED TO 3.0. RAN THE QRH CHECKLIST AND MADE PRECAUTIONARY LANDING. PERFORMED ESM 72-00-00 SUBTASK 72-00-00-700-801. FOUND THE NR 1 ENGINE TO BE OPERATING WITHIN LIMITS. OPS CHECKED GOOD.