SMELL OF GAS AFTER DRIVING FOR ABOUT 20 MIN. LEAD TO A POP SOUND FROM UNDER VEHICLE. SMOKE FILLED THE INSIDE OF THE VAN AND AFTER I BROUGHT IT TO A STOP ON A MEDIAN THE VEHICLE WAS ENGULFED IN FLAMES BEFORE I MANAGED TO EXIT. AFTER EXITING THE VEHICLE AND HAVING THE FIRE PUT OUT SOON ON WITH USE OF A FIRE EXTINGUISHER I NOTICED THE EVAP CANISTER HAD DROPPED ALL OF ITS CHARCOAL. POSSIBLE THAT GAS WAS BEING DIRECTED INTO THIS CANISTER AND WHEN IT POPPED THE FUMES AND GAS IGNITED FROM THE EXHAUST SYSTEM. *JB