Oxygen Sensor Working and Applications

Nowadays, automobile engines can be controlled using different types of sensors. These sensors control the performance & emissions of an engine. When the sensor doesn’t provide accurate data then a lot of problems will occur like drivability, an increase in fuel usage, and failure of emission. One of the essential sensor used in automobiles are oxygen sensor, and the chemical formula of this is o2. The first oxygen sensor was invented in the year 1976 in Volvo 240 vehicle. In 1980, the automobiles in California used these sensors for lower emissions.

What is an Oxygen Sensor?

An oxygen sensor is one type of sensor and it is available in the exhaust system of an automobile. The size and shape of this sensor look like a spark plug. Based on its arrangement in regard to the catalytic converter, this sensor can be arranged before (upstream) or after (downstream) the converter. Most of the automobiles which are designed after 1990 include upstream & downstream o2 sensors.

The oxygen sensors used in automobiles are one sensor is arranged in front of the catalytic converter & one is arranged in every exhaust manifold of the automobile. But, the maximum number of these sensors in a car mainly depends on the engine, model, year. But, most of the vehicles have 4-sensors


Working Principle

The working principle of the o2 sensor is to check the oxygen amount within the exhaust. Firstly, this oxygen was added to the fuel for good ignition. The communication of this sensor can be done with the help of a voltage signal. So the oxygen status in the exhaust will be decided by the computer of the car.

The computer regulates the mixture of fuel or oxygen delivered to the car engine. The arrangement of the sensor before & after the catalytic converter permits to maintain the hygiene of the exhaust & check the converter’s efficiency.

Types of Oxygen Sensors

Oxygen sensors are classified into two namely binary exhaust gas and universal exhaust gas.


1). Binary Exhaust Gas Oxygen Sensor

The binary sensor gives a transition within electric voltage at 350 °C temperature based on the level of oxygen within the exhaust. It contrasts the remaining oxygen content within the exhaust by the ambient air oxygen level & recognizes the change from a lack of air to an excess air & vice versa.

2). Universal Exhaust Gas

This sensor is very exact when calculating the ratios of lack and excess of air or fuel. It has a better calculating range & is also appropriate for employ in gas &diesel engines.

Signs of Faulty Sensor

The faulty sensor can be found by using the following signs.

  • Breakdown to exceed the emissions analysis
  • Fuel mileage can be decreased.
  • The engine light will be off
  • Performance is poor, stalling and rough idling.
  • Code checker recognizing sensor failure


The applications of oxygen sensors include Marine Respiration, Quick Reaction Monitoring, Benchtop R&D, Monitoring of Fuel Tank, Particular Hydrocarbon Environments, Long-term Procedure Monitoring, Fermentation, Packing of Food & Beverage Packaging, Pharmaceutical & Medical, etc.

Thus, this is all about an overview of the oxygen sensor. These sensors are available in two structures like ginger type sensor and planar sensor. Here is a question for you, what are the advantages of oxygen sensor?