As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: PETROLEUM TYPE ODOR INFLIGHT. SUSPECT AIR CONDITIONING SYSTEM. ACCOMPLISHED TASK CARD 26L00021001 INITIAL TROUBLESHOOTING. BOTH ENGINES RUN NO ODOR. FOUND SOURCE OF ODOR IS APU AIR. REMOVED & REPLACED THE APU IAW J/C 26L31049005. PARTIAL WORK ACCOMPLISHED. COMPLETED DECONTAMINATION CARDS 26L00021002 & 26L00021004.