What was found
PHL - FLT 14, ON CLIMB-OUT FROM PHL, PASSING THROUGH FL 200, CREW RECEIVED THE EICAS MESSAGES 'L ENG OVERHEAT'. LIGHT EXITNGUISHED WITH A REDUCTION IN POWER, BUT RETURNED WHEN POWER ADDED. FLIGHT RETURNED TO PHL AND LANDED WITH NO FURTHER INCIDENT. MAINTENANCE SWAPPED THE LEFT AND RIGHT OVERHEAT CARDS, AND STRAIGHTENED A BENT LOOP (10:00 POSITION). (M)