Pontiac G5 Oxygen Sensor
About Oxygen Sensor
Oxygen sensor, also known as Lambda sensor, is an electronic sensor used to determine the amount of oxygen present in any liquid or gas. In automobiles, this sensor has the biggest hand in keeping the performance of the vehicle at its best since it regulates the air fuel ratio which directly affects the power output from the engine based on the data it feeds to the ECU (Electronic Control Unit).
What is the Purpose of Oxygen Sensor?
The oxygen sensor is mounted on the exhaust manifold to measure the unburnt oxygen proportion as the exhaust gases leave the combustion chamber. It's a means to calculate the mixture of air fuel. The machine of a vehicle decides whether the air-fuel mixture is rich (less oxygen) or lean (more oxygen), using this sensor. In modern vehicles, the downstream catalytic converter features a secondary oxygen sensor to track vehicle emissions to comply with the pollution laws.
How Oxygen Sensor Works?
On the end, the sensor has a ventilated cover which screws into the exhaust manifold. Within the cover is a ceramic bulb of zirconium. Across the exterior of the bulb is painted a porous film of platinum. Within the bulb there are 2 platinum strips which serve as electrodes. The outside sensor is exposed to the hot exhaust gas while the inside is ventilated to the ambient atmosphere. A voltage is created by the difference in the oxygen levels in engine exhaust and the outside atmosphere. The ECU receives this induced voltage, and controls the mixture of air-fuel between rich and lean depending on the voltage produced.
Where is Oxygen Sensor Located?
The exhaust manifold holds the oxygen sensors. The one put after the catalytic converter is used to track the output while holding an emissions check. The sensor that is used to measure the air-fuel ratio before the catalytic converter.