Understanding Your Car’s Emissions Control System

Every car is equipped with an emissions control system that works to minimize the hazardous materials produced by your vehicle during operation. The newer your vehicle the more sophisticated the emissions control system is likely to be, with the older vehicles having very limited systems.

There are several components to your vehicles emissions control system, with each part working together to keep your car operating as cleanly as possible. The first part of the emissions control system is the computer that monitors the content of the exhaust produced by the engine. When fuel to air ratios are incorrect the engine is not working at peak efficiency and will produce a lot more hydrocarbons. The emission control system automatically notes this inefficiency and signals the air and fuel intakes to adjust, correcting any problems in the ratio and resulting in a cleaner and more efficient motor. This is all done in real time as the engine is operating, and the driver and passengers are not aware of these constant adjustments and monitoring of the system.

Another part of the emissions control system in your vehicle is the catalytic converter. This is a part of the exhaust system that is located just before the muffler and acts as an additional area where carbon monoxide can be oxidized into water and carbon dioxide. The catalytic converter is designed like a radiator, with a mesh or honeycomb appearance that allows maximum contact of the exhaust with the platinum or palladium in the catalytic converter, resulting in the oxidation as the hydrocarbons touch the metals. During this oxidation process heat is released, resulting in the catalytic converter becoming very hot, sometimes hot enough to almost glow when the exhaust is very dirty and contains high levels of hydrocarbons. When the catalytic converter overheats, this also sends a signal to the car’s computer through the emission control system, resulting in a signal to the driver by a light on the dash or a computer systems test result in newer models.

The third major components in an emissions control system are the various valves located along the exhaust system and during the actual burning of the fuel through combustion. These valves all have to continue to work at the right time and in the right balance to provide optimum performance for the engine. Drivers of newer model vehicles have the luxury of having these valves monitored by the computer on the vehicle, helping with diagnostic tests when fuel mileage and performance is poor. Some of the new models of vehicles even directly email owners with a performance print out that can be taken to a mechanic or even emailed to your repair shop or dealership to keep on file for your next scheduled tune up.