See Figures 1 and 2
A monolithic type 3-way catalytic converter is used to reduce vehicle emissions. The converter, working in combination with the air/fuel ratio, controls the CO, HC and reduces NOx.
Under normal operating conditions, the catalytic converter does not require maintenance. However, it is important to keep the engine properly tuned. If the engine is not kept properly tuned, the catalytic converter may overheat and the converter could be damaged. This situation can also occur during diagnostic testing if any spark plug cables are removed and the engine is allowed to run for an extended period of time.