As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING MAINTENANCE INSPECTION, NOTICED A STRONG ODOR IN COCKPIT WHILE APU BLEED WAS RUNNING. AIRCRAFT REMOVED FROM SERVICE. RAN APU IAW AMM 49-13-00. SUPPLIED APU BLEED AND FOUND NO ODOR NOTED. OPS CHECKED GOOD. FOUND APU OIL OVER SERVICED REF NRWC NR 842-DFW-00901. THE AIRCRAFT WAS RETURNED TO SERVICE.