ABOUT A WEEK PRIOR TO INCIDENT, I GOT A WHIFF OF A BURNING SMELL, 2 DAYS IN A ROW, SHORT QUICK SCENT. NEXT 4 DAYS, SMELLED NOTHING (EVEN DROVE CAR 80 MILES ONE WAY AND BACK). DAY OF INCIDENT, I WAS TRAVELING ABOUT 10 MPH WHEN WHITE SMOKE CAME FROM THE HEATER VENT. I INCREASED SPEED TO ABOUT 30 MPH TO GET TO A SAFE SPOT, AND BLACK SMOKE BILLOWED OUT OF HEAT VENT ON TOP OF DASHBOARD, AND FRONT OF DASHBOARD. TURNED CORNER TO GET OUT OF TRAFFIC, CAME TO A STOP AND FLAMES SHOT OUT OF CIGARETTE LIGHTER, AND AIR VENT IN FRONT OF DASH. HEATER WAS OFF, RADIO WAS OFF, AND CIGARETTE LIGHTER WAS NOT BEING USED. CAR FULLY ENGULFED IN APPROXIMATELY 2-3 MINUTES. CAR TOTALED. *TR