Preventive Maintenance for Catalytic Converters
One-wire and two-wire "unheated" type oxygen sensors should be check or replaced ever 30,000 to 50,000 miles. These sensors rely solely on hot exhaust gas to heat up to operating temperature, and are designed to allow a large volume of exhaust gas to make contact with the active ceramic element. These sensors are exposed to contamination, especially the "wide-slot" varieties found on Chrysler, Ford and General Motors vehicles.
"Heated" type oxygen sensors have a built-in heater which heats the sensors. Much less exhaust gas needs to contact the ceramic element, making these sensors less prone to contamination.
"Heated" type sensors can also be located further downstream, (closer to the catalytic converter), which increases their life expectancy. "Heated" type oxygen sensors should be checked or replaced every 60,000 to 100,000 miles.
Click here to go back to About Catalytic Converters.