As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN FLIGHT, THE PILOT NOTICED AN OILY HAZE IN THE COCKPIT AND CABIN. THE PILOT SECURED THE NR 1 ENGINE BLEED WHICH SEEMED TO DISIPATE THE HAZE. THE AIRCRAFT RETURNED TO THE FIELD WITH AN UNEVENTFUL LANDING WHERE MAINTENANCE TROUBLESHOT THE PROBLEM. ON 8/13 MAINTENANCE REMOVED AND REPLACED THE NR 1 ENGINE.