How Does an Oxygen Sensor Work?

An oxygen sensor is a device capable of measuring the proportion of the oxygen atom in some fluid. This device or sensor is almost always used in cars. They are placed in the exhaust pipes and measure the proportion of oxygen in the gases resulting from the combustion carried out in the engine.

These devices are essential in cars because they can measure the oxygen of the gas combustion products to verify how proper the combustion has been. And in the case of not having been right, send a signal notifying.

Operation of an oxygen sensor

• An oxygen sensor works by comparing the proportion of oxygen in gases, with 21%, which is the proportion of oxygen in the atmosphere. This comparison can be made because the sensor generates a millivoltage from the presence of oxygen
• There are two types of sensors. The conventional, where the heart of this sensor is shaped like a thimble, and the planar, made of a ceramic material, covered internally and externally by a layer of microporous platinum.
• A motor burns fuel -gasoline or diesel- in the presence of oxygen. There is an exact ratio of both air and petrol so that the mixture of both is “perfect” (the rate depends directly on the type of fuel – that is, how much hydrogen and coal it can have). In the first case, if there will be little air in the combination, then you have a surplus of fuel after the ignition, this is called a rich mixture. This isn’t good because the unburned fuel pollutes the environment. Now in the second event, if there are more air and less fuel, then you have an excess of oxygen; this is called a weak mixture. This tends to generate more nitrogen oxide pollutants and, in some cases, cause low performance, including damage to the engine.
• The oxygen sensor is placed in the exhaust pipe and serves to detect rich or poor mixtures. The mechanism in most sensors involves a chemical reaction that generates a voltage. The engine computer monitors this voltage to determine if the mixture is rich or lean, thereby adjusting the amount of fuel that must enter the engine.
• An oxygen sensor is necessary to be able to measure the amount of air that the engine sucks, this is important since it depends directly on factors such as the altitude, the temperature of the environment and the same machine, the barometric pressure, the load that has the engine, etc.
• When the oxygen sensor fails, the computer can no longer detect the air/fuel range, so it ends up guessing what it is. With this, the car performs poorly and uses more fuel than it requires.

An essential piece to save fuel

Motorists know the importance of checking and maintaining certain parts such as tires but are not necessarily aware of the existence of oxygen sensors, their usefulness, and location. They do not know that these sensors are located in the line of the exhaust system.

The electrodes of the probe composed of Yttria and Zircon, make it possible to measure the oxygen content of the combustion gases and to transmit the information to the computer of management of the engine. The latter can then deduce the amount of ideal fuel to be injected into the cylinders to adjust the air/fuel mixture.

The operations counselors should emphasize the importance of this piece that reduces emissions, but also fuel consumption.

Life of an oxygen sensor

A faulty oxygen sensor can have a considerable impact on the increase of polluting discharges and lead to overconsumption. On average, it is estimated that the life of the part is about 160,000 km when regular maintenance is done.

After training to become an advisor to automotive services, several clues will help you know if a customer’s vehicle requires a check or a sensor change. If the customer complains of a lack of power, uneven idling, and the Check Engine light on their vehicle is on, the oxygen sensor is likely the cause.

What it does check before considering a replacement

Several factors can have an impact on the deterioration of a probe. It is, therefore essential, before considering a replacement to ensure impeccable maintenance of the engine. Also, it is possible to disassemble the sensor to check its status. The fouling of the part makes it possible to determine if the problem is related to a leak in the combustion chambers or overconsumption of oil.

Finally, a faulty sensor is also detected with the diagnostic tool that is connected to the vehicle. If all the elements that can have an impact on the probe are checked correctly and that they present no problem, it is then possible to consider a replacement of the part.