What was found
CREW REPORTED SMOKE IN CABIN. AIRCRAFT RETURNED TO GATE. REPLACED COALESCER BAGS, INSPECTED PNEUMATIC SYSTEM, PERFORMED ENGINE RUNS, AND NO DEFECTS NOTED. FOUND LEFT ACM WITH EVIDENCE OF SEAL LEAKAGE BETWEEN CASE HALVES, REMOVED AND REPLACED ACM. ALSO REMOVED AND REPLACED FLOW MULTIPLIER DUE TO EVIDENCE OF SEAL LEAKAGE BETWEEN CASE HALVES.