Due to a federal requirement for an additional warrant of emissions equipment including the catalytic converter, it is prudent to consult the dealer service department before replacing the converter at an individual's own cost. To curb emission of hydrocarbon, carbon monoxide, and oxides of nitrogen all vehicles are fitted with three way catalyst system which oxidize and reduce the above said chemicals and changes them into harmless nitrogen, carbon dioxide and water. As for the exhaust system, the catalytic converter is placed in the system just like a muffler is placed. Using a wrench, check the converter-to-exhaust pipe mating flanges and the bolts of the two; discover whether there are any loose bolts or whether there are any leaks between the flanges. Inspect for damages to the catalytic converter protector; if any part comes in contact with the converter because it is damaged or dented, fix or get a new one. Also, check the heat insulator(s) for signs of wear and tear, there should also be enough space between the heat insulator and the catalytic converters.