As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW DIVERTED THE AIRCRAFT TO A SAFE LANDING AT IAD DUE TO FUMES IN CABIN AND COCKPIT DURING CLIMB-OUT. NO VISIBLE SMOKE AND ODOR SMELLED OF ENGINE EXHAUST AND WAS NOT ELECTRICAL. ODOR WAS WORSE AT HIGHER POWER SETTINGS. MAINTENANCE INSPECTED BUT NO LEAKS WERE LOCATED. PNEUMATIC SYSTEM TROUBLESHOOTING CHECKED GOOD. A DUCT SYSTEM BURNOUT WAS PERFORMED AND THE WATER SEPARATOR BAGS WERE REPLACED.