AS I WAS DRIVING DOWNHILL ON I-15 JUST 3 MILES SOUTH OF SCIPIO, UT, I BEGAN TO NOTICE ISSUES WITH THE BRAKES AND ACCELERATOR. I GOT INTO THE FAR RIGHT LINE OF THE HIGHWAY AND NOTICED THAT SMOKE AND FLAMES CAME FROM UNDERNEATH THE HOOD. AS I PUT THE CAR IN PARK, THICK BLACK SMOKE CAME THROUGH THE AIR VENT. AS WE GOT OUT OF THE VEHICLE, I BREATHED IN A LITTLE BIT OF THE THICK SMOKE THAT CAME THROUGH THE AIR VENT, BUT MY WIFE DID NOT BREATHE ANY OF THE SMOKE. THE HOOD AREA WAS COMPLETELY ENGULFED IN FLAMES AFTER WE ESCAPED FROM THE VEHICLE. THE FIRE DEPARTMENT PUT OUT THE FIRE ABOUT 20 MINUTES AFTER THIS INCIDENT STARTED. EVERYTHING FROM THE FRONT OF THE CAR TO ABOUT HALF OF THE TRUNK AREA WAS DESTROYED.