As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED. FLIGHT ATTENDANTS REPORTED SULFUR SMELL MID CABIN. MAINTENANCE FOUND THE APU OIL LEAKING OIL FROM THE COOLING FAN, INGESTION INTO THE LOAD COMPRESSOR VERIFIED SINCE THE INTAKE AND DIFFUSER WERE OIL SOAKED. REPLACED COOLING FAN AND ACCOMPLISHED A SATISFACTORY LEAK CHECK PER AMM 49-52-51. MAINTENANCE COMPLIED WITH JOB CARD'S 26L00021001 T/S CABIN AIR QUALITY, 26L00021002 APU SMELL IN CABIN, 26L31049009 CLEAN APU COMPRESSOR AND 26L00021004 DECONTAMINATION OF THE ECS ENGINE AND APU. (EVENT RE-OCCURED SEE AALA201611049004 AND AALA201611079015).