WHEN SLOWING DOWN ON HWY EXIT RAMP, CAR MADE THREE QUICK POPPING SOUNDS AND STARTED SMOKING. PULLED OFF ROAD AND MORE SMOKE CALLED 911. THE CAR DASH CAUGHT FIRE AND CAR INTERIOR BURNED BEFORE FIREFIGHTERS COULD PUT IT OUT. FIREFIGHTER SUGGESTED IT COULD BE A TRANSMISSION LINE? NEVER HAD ANY TRANSMISSION TROUBLE PREVIOUSLY.