TL*THE CONTACT OWNS A 2000 MERCURY GRAND MARQUIS. THE CONTACT STATED THE HE SMELLED A BURNING ODOR. THE CONTACT LOOKED AT THE TEMPERATURE GAUGE WHICH INDICATED THAT THE VEHICLE HAD OVERHEATED. THE VEHICLE WAS TAKEN TO AN INDEPENDENT MECHANIC WHERE THE CONTACT WAS INFORMED THE INTAKE MANIFOLD WAS MADE OF PLASTIC AND WAS LEAKING. THE LEAK WAS SEALED, BUT THE CONTACT WAS INFORMED THAT THE REPAIR MAY NOT HOLD UP FOR A LONG PERIOD OF TIME. THE FAILURE MILEAGE WAS 100,000 AND THE CURRENT MILEAGE WAS 103,000. THE VIN WAS UNAVAILABLE.