As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 4096 (DTW TO TYS) STRONG ODOR OF FUEL EACH TIME TRANSFER PACKS TO APU BOTH WHILE ON THE GROUND AND AIRBORNE. FOUND RESIDUAL FUEL IN APU COMPARTMENT. CLEANED COMPARTMENT. LEAK CHECKED APU-NO LEAKS NOTED. RUN LEFT & RIGHT PACKS FROM ENGINES AND APU. FOUND NO ODOR PRESENT. LEAK CHECKED IAW AMM 49-31-01.