What was found
SEC ENG START AND BUS XFER WHITE SMOKE ACRID SMELL ON FO SIDE VE NT UNDER WINDOW T/S AS PER AMM: 05-51-26-800-C1, STEP C: INITIAL INSP & OPS CHECKS AND DETAILED INSP & OPS CHECKS. LOAD SHED TEST OPS OK. COULD NOT DUPLICATE FAULT. NO EVIDENCE OF SMOKE IN CABIN OR COCKPIT IAW AMM. REF: STEP E DISPOSITION OF EVENT. ACCOMPLISHED REPLACEMENT OF BOTH RECIR. FILTERS IAW AMM 21-25-01-000-801. PERFORMED OPS TEST IAW 710-802-002. OPS CHKD GOOD. OK FOR SERVICE.