WHILE DRIVING 30MPH & STARTED TO SMELL AN ODOR INSIDE VEHICLE. SMOKE WAS COMING THROUGH THE VENTS. PULLED TO SIDE OF ROAD & RETRIEVED THE FIRE EXTINGUISHER. AFTER LEAVING VEHICLE, IT WAS ENGULFED IN FLAMES. FIRE DEPARTMENT CALLED & PUT OUT FLAMES. WAS EXTENSIVE DAMAGE DONE TO VEHICLE. FIRE DEPARTMENT SUSPECTED FIRE WAS CAUSED BY A SHORT IN ELECTRICAL WIRINGS, BUT NOT DEFINITE DUE TO DAMAGE.*AK