What was found
SIG EVENT - THE PILOT REPORTED THAT UPON LANDING SMOKE STARTED POURING OUT OF THE VENTS, AT THAT TIME THEY TURNED THE LEFT PAC OFF. MAINTENANCE RAN THE LEFT PAC FOR 45 MINUTES IN LOW AND NORMAL SETTING, COULD NOT DUPLICATE THE PROBLEM, NO SMOKE OF ANY KIND WAS NOTED, OPERATIONAL CHECKS GOOD IAW EMB MM 21-00-00.