As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED A HEAVY OIL SMELL COMING FROM THE NR 1 AIR CONDITIONING PACK. NR 1 PACK WAS PUT ON MEL AT THIS TIME. MAINTENANCE COULD NOT DUPLICATE DISCREPANCY. AN OPERTATIONAL CHECK OF BOTH PACKS WAS COMPLIED WITH , NO SMELL NOTED. AIRCARFT WAS RETURNED TO SERVICE.