What are o2 sensors?

An o2 sensor, sometimes referred to as a lambda sensor, is an electronic mechanism that estimates the percentage of oxygen in the gas or liquid that is being evaluated. It was first developed by the Robert Bosch GmbH company in the latter parts of the 1960s under the administration of Dr. Günter Bauman. Oxygen sensors that was used for automotive applications is the most commonly used oxygen sensor and it is used to evaluate the exhaust gas concentration of oxygen for internal combustion engines in automobiles and other motor vehicles. Drivers also use a device that is similar to the oxygen sensor to analyze the partial pressure of oxygen in their breathing gas.
These oxygen sensors, which are more commonly known colloquially as O2 sensors, make contemporary electronic fuel injection and emission management achievable. They are very helpful in establishing, in real time, if the air fuel ratio of a combustion engine is rich or weak. As oxygen sensors are positioned in the exhaust stream, they are not completely involved in measuring the air or the fuel flowing into the engine. However when the information from the oxygen sensors is combined with the information from other sources, it can be utilized ultimately to assess the air-to-fuel ratio.

Oxygen sensors do not really measure oxygen concentration, but rather they measure the quantity of oxygen that is required to fully oxidize any lingering combustibles in the exhaust gas. Rich mixture brings about an oxygen demand. This oxygen requirement causes a voltage to build up, owing to the movement of oxygen ions through the sensor layer. Lean or rich mixture causes low voltage because there is an excess of oxygen.

Present spark-ignited combustion engines use oxygen sensors and catalytic converters so as to lessen exhaust emissions. The information that is collected on the oxygen concentration is transported to the engine management computer or ECU (Engine Control Unit). This regulates the quantity of fuel injected into the engine to balance for excessive air or fuel. Generally, The ECU looks to maintain an accurate air-fuel ratio by construing the information it gets from the oxygen sensors. The most important objective is to cooperate between fuel economy, power and emissions.