I TOOK MY CAR INTO THE SERVICE DEPARTMENT DUE TO A STRONG SMELL OF PROPANE/NATURAL GAS. THE SERVICE WRITER INFORMED ME THAT THE SMELL WAS REALLY BAD BUT THAT IT SHOULD BE SAFE TO DRIVE AND THAT SHE COULDN'T GET ME IN UNTIL TUESDAY. I BUCKLED MY 2 YEAR OLD IN THE CAR SEAT AND LEFT THE DEALERSHIP/SERVICE DEPARTMENT. THE SERVICE WRITE STATED THAT THERE WAS A TSB OUT ON THE CAR AND IT COULD BE A POSSIBLE LEAK IN THE PTU. BUT SHOULD BE THAT BIG OF DEAL. WE STARTED TO TRAVEL HOME THE CAR STALLED, ON A HIGHWAY TRAVELING AT ABOUT 60 MILES PER HOUR, AND THERE WAS A LOUD POP, I WAS ON THE PHONE WITH MY SISTER WHO WAS TRAVELING BEHIND US WHO TOLD ME THAT MY CAR WAS ON FIRE AND TO PULL OVER. I STOPPED THE CAR, WHEN I WAS STOPPED THE INTERIOR OF THE CAR FILLED WITH SMOKE I RUSHED TO GET MY CHILD OUT OF THE CAR AND MOVED AWAY FROM THE CAR. I DIDN'T SEE ANY FLAMES JUST A LOT OF SMOKE. I FEEL WE WERE LUCKY BECAUSE MY SISTER WAS ABLE TO INFORM ME IMMEDIATELY THAT THERE WAS SMOKE. I FEEL THAT IF I WOULD HAVE DRIVEN THE CAR MUCH FURTHER THE OUTCOME COULD HAVE BEEN MUCH DIFFERENT.