The oxygen sensor in your vehicle is an electronic component that is designed to measure levels of oxygen in the engine exhaust. Typically, the oxygen sensor is mounted to the exhaust system tube, with the sensor part inside the tube. This measures the oxygen mixture by generating a small amount of electricity due to the difference in atmosphere, oxygen and carbon dioxide. The PCM monitors this voltage and adjusts the fuel system and engine timing accordingly.
The oxygen sensor is in continuous communication with the engine control unit giving it the information necessary to adjust fuel intake and ignition timing for correct combustion. When the engine is cold the oxygen sensor is not as active, but will become so after the engine coolant has reached a specific temperature. Early sensors used this time to “heat” up so that the reactive material within could work properly, to correct this condition the oxygen sensor has been constructed with a 12 volt heater element. This heater allows the sensor to read at maximum efficiency quicker. When the throttle is wide open and under max load the oxygen sensor will go full voltage until normal operating conditions return. Typically changing an oxygen sensor when necessary is a simple process. Most solutions to oxygen sensor problems result in changing the oxygen sensor, but always be sure there are no vacuum leaks present in the intake
system, this can give a false oxygen sensor trouble code Due to the severe usage the sensor endures, it is common for most sensors to last approximately 75,000 miles, however it is not uncommon for an oxygen sensor to last only 40,000 miles depending on your driving habits and vehicle conditions.
Oxygen Sensor Cut Away
Over the life of the oxygen sensor soot build up can occur on the sensing probe which can result in inaccurate readings. This can cause your engine to run rough and consume excessive fuel. Remove the sensor and replace it with a new sensor.