Total Car Care Centers is a full service independent auto repair facility serving the greater Portland, Oregon area.

Check Us Out!

Check Us Out!

Our Technicians Are

We use only quality brand Name spark plugs in our service department!

We Use Only Quality Brand Name Spark Plugs!

Save Big With

Coupons!

Catalytic Converters

How The Catalytic Converter Works

A three-way catalytic converter: Note the two separate catalysts.

There are two main types of structures used in catalytic converters -- honeycomb and ceramic beads. Most cars today use a honeycomb structure.

Ceramic honeycomb catalyst structure.

The Reduction Catalyst

The reduction catalyst is the first stage of the catalytic converter. It uses platinum and rhodium to help reduce the NOx emissions. When an NO or NO2 molecule contacts the catalyst, the catalyst rips the nitrogen atom out of the molecule and holds on to it, freeing the oxygen in the form of O2. The nitrogen atoms bond with other nitrogen atoms that are also stuck to the catalyst, forming N2.

The Oxidization Catalyst

The oxidation catalyst is the second stage of the catalytic converter. It reduces the unburned hydrocarbons and carbon monoxide by burning (oxidizing) them over a platinum and palladium catalyst. This catalyst aids the reaction of the CO and hydrocarbons with the remaining oxygen in the exhaust gas.

Where did this oxygen come from?

The Control System

The third stage is a control system that monitors the exhaust stream, and uses this information to control the fuel injection system. There is an oxygen sensor mounted upstream of the catalytic converter, meaning it is closer to the engine than the converter is.
This sensor tells the engine computer how much oxygen is in the exhaust. The engine computer can increase or decrease the amount of oxygen in the exhaust by adjusting the air-to-fuel ratio. This control scheme allows the engine computer to make sure that the engine is running at close to the stoichiometric point, and also to make sure that there is enough oxygen in the exhaust to allow the oxidization catalyst to burn the unburned hydrocarbons and CO.

We give our thanks to HOW STUFF WORKS for allowing us to use their info and graphics!
For more information on how engines or anything else in this world works, visit www.howstuffworks.com.

Here at Total Car Care Centers we have all the services your vehicle needs to keep running smoothly.

Oil changes, transmission flushes, cooling system flushes, air filters, & fuel filters are just a few of the many services & products we offer!.

We install quality rebuilt and/or used engines. We also perform minor repairs that don't require engine removal.

CALL FOR APPOINTMENT

503-266-2700

[ Welcome Page ] [ Contact Us ] [ Directions ] [ Company History ] [ Copyright ] [ Disclaimer ]