As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT DESCENT, SMELLED TURBINE OIL FROM THE AIR VENTS. NO HAZE OR SMOKE NOTED. ONLY IN CONTROL CABIN, NO SMELL IN PASSENGER AREA. FOUND CONTAMINATION & HIGH VIBRATION AT NR 1 ACM. INSPECTED IAW MM. DEFERRED NR 1 ACM PER MEL. R&R ACM PER MM.