As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN FLIGHT, CABIN AND COCKPIT FILLED WITH SMOKE VISIBLE WITH ODOR. SMELLED LIKE SMOKING OIL OR OVERHEATED DUCTING NO COCKPIT INDICATIONS OF PROBLEM. REMOVED AND REPLACED ACM AND HEAT EXCHANGER. OPERATIONAL TEST IN ALL MODES NORMAL. AIRCRAFT RETURNED TO SERVICE. (M)