As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 3106 - DURING CRUISE EN ROUTE FROM DTW TO YOW, THE CREW NOTED OILY SMOKE COMING FROM THE BLEED AIR SYSTEM. THE CREW SHUT DOWN BOTH BLEEDS AND RETURNED TO DTW WITHOUT INCIDENT. MAINTENANCE REPLACED THE NR 1 N1 PROBE O-RINGS. THE SYSTEM OPERATED SATISFACTORILY. (M)