What was found
IAH - FLIGHT 3144, DURING PRE-FLIGHT INSPECTION THE CREW REPORTED A FUEL SMELL COMING FROM THE APU. MAINTENANCE INSPECTED THE AIRCRAFT, AND PLACED THE APU ON MEL 49-00-00 CTL#143170 CAT C, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE. ON 04/09/08, IAH MAINTENANCE OPERATIONALLY CHECKED THE APU WITH NO SMELL OR DEFECTS NOTED, REMOVED THE MEL, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.