VEHICLE IDLING AT DRIVE THRU; SMELLED FUNNY ODOR, LIKE ELECTRICAL WIRES; PULLED OUT OF LINE & TURNED VEHICLE OFF; LIFTED HOOD & NOTICE ALTERNATOR & WIRES IN FLAMES; GOT FIRE EXTINGUISHER FROM MCDONALD'S & PUT FLAMES OUT. GOT WIRES FROM DEALER & ALTERNATOR FROM PARTS STORE & REPLACED THEM; STILL HAVE OLD PARTS.