Because of a longer warranty required by the federal government for emissions-related parts and devices, such as a catalytic converter, one should turn to a dealer service department before replacing the converter on one's personal dime. All vehicles are fitted with a sociable- a three- way catalyst system that treats the exhaust gases oxidizing and reducing the hydrocarbon, carbon monoxide, and oxides of nitrogen to harmless nitrogen, carbon dioxide, and water respectively. It is wrapped around the exhaust manifold and welded directly onto the manifold in some models while its location is the exhaust system similar to a muffler in other models. The following areas should be inspected periodically: the woodruff key, the down pipe, and the catalytic converter mating flanges and bolts for signs of looseness and leaks. Also, the catalytic converter protector should be examined for dents or other signs that any part of it touches the converter; if this is the case, the part should be fixed or replaced. Last but not the least; examine the condition of the heat insulator and make sure that there is sufficient space between the heat insulator and the catalytic converter.