DRIVING AT NORMAL SPEED (45 MPH), NO ABNORMAL NOISES OR VIBRATIONS PRESENT. LOUD BANG NOISE CAME FROM WITHIN ENGINE BAY, AND TRUCK BEGAN TO SPUTTER AND STUMBLE VERY BADLY. CHECK ENGINE LIGHT CAME ON AND PRECEDED TO FLASH, PUT TRUCK INTO NEUTRAL AND ROLLED TO THE SIDE OF THE ROAD WHERE TRUCK WAS SHUT OFF. EXCESSIVE FUEL WAS FOUND ON TOP OF THE ENGINE AT THE THIRD CYLINDER FROM THE FRONT ON THE PASSENGER SIDE (4.6L V8 ENGINE). SPARK PLUG WAS SEPARATED FROM THE WIRE AND LYING ON TOP OF ENGINE. SPARK PLUG BOOT WAS MELTED AND SMOKING SUGGESTING IT WAS PREVIOUSLY BURNING. SPARK PLUG WAS %100 COVERED BY BURNT SOOTY MATERIAL. *TR