LOUD EXPLOSION FROM ENGINE COMPARTMENT. THEN, SPARKS WITH FLAMES BEGAN, WHILE DRIVING ON THE STREET. OTHER DRIVERS WAIVED & ALERTED US THAT FLAMES WERE COMING OUT. WE STOPPED & GOT OUT. THERE WAS A TRAIL OF OIL BEHIND. APPROX. 75 FT LONG. CHUNKS OF ENGINE METAL WAS RECOVERED OFF THE ROAD.