As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK-- NR 2 OIL FILTER BYPASS LIGHT ILLUMINATED ON DEPARTURE. EXTINGUISHED WHEN POWER REDUCED BELOW APPROX 30 PERCENT N1. POWER ADVANCED TO APPROX 45-55 PERCENT N1 AND LIGHT BACK ON. EXTINGUISHED AGAIN WITH POWER REDUCED. REMOVED AND REPLACED NR 2 ENGINE PER MT.