As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOTS REPORTED THAT THERE WAS A LINGERING, FOUL, MOLDY STENCH IN THE COCKPIT AND CABIN. THOUGHT TO BE COMING FROM THE BLOWER VENTS. THE ODOR WAS NOTED AS VERY NAUSEATING AND FATIGUING FOR THE CREW TO FLY IN. MAINTENANCE CLEANED AREAS FORWARD AND AFT OF THE MAIN SPAR UNDER FLOOR. REMOVED BROWN SMELLY SUBSTANCE WITH ALCOHOL AND A SCRUBBER PAD. APPLIED CPC TO CLEANED AREAS.