Our featured repair today is Oxygen Sensor Replacement on a 2005 Mazda 3.

Oxygen sensors are a frequently replaced item on many vehicles.
The function of the oxygen sensor is to inform the engine computer of the oxygen content in the exhaust. Depending on the oxygen content the computer knows whether the fuel mixture is rich or lean and will make appropriate adjustments to the fuel injection system.
Today’s Mazda 3 came in because the check engine lamp was on. After scanning and diagnosis we found the front oxygen sensor dead. This vehicle has two oxygen sensors, one before the catalytic converter and one behind. The front sensor monitors the engine out emissions while the rear sensor monitors the catalytic converter’s efficiency.
Overall Mazda 3s are a very reliable vehicle and oxygen sensors are one of the few parts that fail on these vehicles.
To read more about the Mazda 3 click on this link http://en.wikipedia.org/wiki/Mazda_3
To learn more about oxygen sensors click this link http://en.wikipedia.org/wiki/Oxygen_sensor
