The air oxygen sensor is a vital component of your car’s engine. It monitors the amount of oxygen in the exhaust to help ensure that your vehicle’s catalytic converter is working properly. It also helps control the fuel mixture so that your engine is operating at a healthy stoichiometric condition. This helps reduce hydrocarbon and nitrogen oxide emissions that cause environmental damage.

The oxygen sensor is a ceramic cylinder that has been plated inside and out with porous platinum electrodes. When the sensor is exposed to a gas sample, the oxygen molecules absorb electrons from the electrodes, which generates a voltage that can be read by the vehicle’s ECU. The sensor’s output signal is either high or low depending on the oxygen concentration of the gas being tested.

Narrowband Oxygen Sensors

The air oxygen sensor is the most common type found in vehicles. The sensor is designed to measure a small range of air-fuel ratios in the engine’s exhaust gases. It works by measuring the difference between oxygen concentration in the exhaust gases and in the atmospheric air. The O2 sensor produces a signal that tells the engine’s ECU to adjust the engine fuel delivery and ignition timing if the exhaust is too rich or too lean. A too rich fuel mixture can produce unburned fuel and carbon monoxide, while a too lean fuel mixture can produce hydrocarbons and nitrogen oxide pollutants.

Wideband Zirconia Oxygen Sensor

The wideband zirconia oxygen sensor is an alternative to the narrow band oxygen sensor and has been used in cars for a number of years now. The sensor is similar to the narrowband sensor, but it has a larger sensing area and provides a wider range of measurements. This helps eliminate the lean-rich cycling that is inherent in narrowband oxygen sensors, allowing for more accurate and gradual mixture adjustment.