WAS DRIVING ON HIGHWAY APPROXIMATELY 65 MPH WHEN THE ENGINE FAULT CAME ON AND LOST POWER. PULLED TO SIDE OF ROAD AND BEGAN TO SEE SMOKE FROM ENGINE. FIRST THOUGHT WAS OVERHEATING OR SIMILAR. WITHIN MINUTES NOTICED FLAMES FROM UNDER HOOD NEAR WINDSHIELD. GOT OUT OF CAR AND WITHIN LESS THAN 5 MINUTES CAR WAS FULLY ENGULFED IN FLAMES. THIS WAS AN OBVIOUS ENGINE ISSUE AND NOT A MAINTAINANCE ISSUE. THIS WAS A FLEET VEHICLE PROPERLY MAINTAINED UNTIL I PURCHASED IT FROM THAT EMPLOYER 1 YEAR PRIOR.