What was found
FUMES IN COCKPIT, NO SMOKE, NO EMERGENCY DECLARED. RAN BOTH ENGS FOR 35 MINS WITH BOTH DUCTS OPERATING WENT TO FULL HOT AND COLD. INSPECTED ENG INLETS RAN AIR INLETS & EXHAUSTS INSPECTED BOTH ACM'S ALSO USED APU AIR WENT FULL HOT & COLD. RAN ENG ABOVE IDLE AND AT IDLE USING PACK OPERATION. UNABLE TO DUP PROBLEM. USED THE FOLLOWING MM REF 21-53-01-6, 21-45-11-4, 21-45-12-4, 21-22-00-0.