Your exhaust produces harmful emissions of hydrocarbons, carbon monoxide and nitrogen oxides that are damaging to the atmosphere if released into the air.
A catalytic converter substantially reduces the amount of harmful pollutants by taking these gases and converting them into water vapor and less harmful gases via a series of chemical reactions. All gas cars manufactured since the early 1990’s requires having a catalytic converter fitted to the exhaust.
The catalytic converter includes a core of ceramics spotted with pores that measure less than 1mm. The pores are coated with powdered catalysts that contain metals such as platinum, palladium and rhodium. Because the pores are close to the engine they heat up and the chemical structure of the exhaust gases passing though it changes so that harmful gases that cause smog are removed and converted into nitrogen and oxygen. Converters are so efficient that the difference in emission readings for cars with converters and those without are considerable. The good news is that catalytic converters are expected to have a good life, but still need to be checked periodically for internal and external damage.
Catalytic converter issues can lead to increased exhaust emissions and a decrease in engine performance. Most issues stem from temperature changes in the exhaust system. Excessive unburnt fuel in the exhaust can cause the catalyst to reach extremely high temperatures which can cause damage to the fine catalyst material. (An engine that is performing at peak efficiency will burn all the fuel in the combustion chamber during the combustion process. An engine that is not performing properly, that is not burning all the fuel, will allow unburned or excess fuel to enter the exhaust system. When this excess or unburned fuel contacts the hot core of the converter it will ignite.) As a result, the catalytic converter becomes less effective, less chemical conversions take place and the exhaust output contains more harmful gases.
Similarly, rapid cooling of the catalytic converter, such as by being submerged in water, can cause the internal honeycomb structure to break apart and obstruct the exit to the exhaust pipe. If the catalytic converter becomes plugged, engine efficiency will decrease noticeably.
There are ways to keep your CAT Clean, remember that having a CAT on your car is a necessity and is a violation of the Clean Air Act not to have one, even off roading.
Keep your CAT clean and your environment beautiful!