What is the function of the car oxygen sensor, why some cars are installed with two sensors

As an important component of the closed-loop control of electronically controlled engine fuel injection, in order to meet emission regulations and improve the fuel economy of the vehicle, the front oxygen sensor (before the three-way catalytic converter) is mainly used to detect the oxygen content in the exhaust gas emitted after the combustion of the cylinder. >1 (is the ratio of the actual air-fuel ratio to the theoretical air-fuel ratio), at this time, the feedback voltage of the oxygen sensor is sent to the ECU. According to the calculation result of the mixture being too thin, the ECU increases the injection volume (that is, the injection pressure is constant, and the injection time is extended), and vice versa, the injection volume is reduced. (Note that the engine does not have closed-loop control in some operating conditions, that is, the fuel injection volume is adjusted without reference to the front oxygen sensor, such as full acceleration conditions). The rear oxygen sensor is mainly used to detect the oxygen content after the three-way catalytic converter, which is the main purpose of detecting the working effect of the three-way catalytic converter and detecting whether the emission meets the standard.

Because the gasoline engine uses the front oxygen sensor to detect the oxygen content in the exhaust to adjust the amount of fuel injection, and the rear oxygen sensor to detect the efficiency of the three-way catalytic converter, the two oxygen sensors have different functions, so the hydrogen oxygen sensor is designed.

Hello, cars generally have two oxygen sensors, the front of the three-way catalytic converter is the front oxygen sensor and the rear oxygen sensor. Purpose:1

The front oxygen sensor detects the oxygen content in the exhaust gas to check whether the mixture is thin or concentrated. In the form of an electrical signal (change between pay-to-pay) to the engine computer. Constant adjustment to maintain a consistent concentration of the mixture at:

1. This concentration is when the efficiency of the three-way catalytic converter is at its highest. Exhaust emissions meet environmental protection requirements.

2.The rear oxygen sensor is to detect whether the three-way catalytic converter is working well or badly. If the exhaust gas is not well reduced to the standard gas, the voltage of the rear oxygen sensor does not meet the standard, high or low, or wavy, and the three-way catalytic converter fails.

At this time, the engine computer records the fault record fault P0420, and the engine fault light is lit.

Hello, generally cars are equipped with two oxygen sensors, located in front of the three-way catalytic converter is the front oxygen sensor, and behind is the rear oxygen sensor.

Hello, this depends on the vehicle configuration, generally four cylinder vehicles have two oxygen sensors, this one is the front oxygen and one rear oxygen.

2, front oxygen sensor and rear oxygen sensor,

The engine emission test is fed back to the computer for fine-tuning. The front of the three-way catalysis is to regulate the engine, and the back is to detect the emissions.

The front oxygen sensor is used for monitoring.

Corrected the amount of fuel ** in the engine to improve engine performance and reduce fuel consumption.

The rear oxygen sensor is used to detect whether the three-way catalytic converter is faulty and whether the exhaust emissions meet the standard.

The oxygen sensor mainly detects the oxygen content in the exhaust gas, adjusts the fuel injection through data, and controls the operation of the engine.

The oxygen sensor is used as a feedback signal for the EFI system, and is used as a feedback signal to correct the pulse width of the fuel injection to control the discharge.

Oxygen sensors are not involved at all times.

For example, the start-up condition.

Rapidly accelerate the warm-up ......

In addition, its performance is best at 300 degrees Celsius, and the rear oxygen sensor monitors the conversion rate of the three-way catalytic converter.

It is compared with the signal of the front oxygen sensor.

to determine whether the three-way catalytic converter fails.

Two is not specific, the number depends on the position, if there is one before and after the three-way catalytic converter, this is another form. The function of the oxygen sensor is to monitor the oxygen content in the exhaust gas discharged by the engine, and the oxygen molecules in the exhaust gas indicate that the mixture is too thin, and then the computer will supply a thicker mixture, which is the simple function.

Detect the oxygen content in the exhaust gas, feedback to the computer in time, correct the fuel injection volume, and control the emission.

Two are installed to better control emissions, and the latter one has the role of supervising the previous one.

The function of the oxygen sensor is to determine whether there is excess oxygen in the exhaust gas of the engine after combustion, and convert the oxygen content into a voltage signal and transmit it to the engine computer, so that the engine can realize the closed-loop control with the goal of excess air factor; Ensure that the three-effect catalytic spine renter has the maximum conversion efficiency for the three pollutants in the exhaust gas, namely hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NOX), and maximize the conversion and purification of the emitted pollutants. Precautions for using oxygen sensors: 1. Try to drive as smoothly as possible.

Unless it is an emergency or bad road conditions, it is necessary to minimize the violent shaking and impact of the car body, and avoid the bottom of the car chassis (especially near the rear row). Because there are ceramic sensitive components in the oxygen sensor, these components can be damaged by severe shaking or impact.

2. Pay attention to the sensor wire wire. When overhauling the vehicle, it is necessary to pay attention to the line and try not to pull excessively. Sensors, like other electronic devices, can affect the proper operation of the oxygen sensor if their wires are affected, resulting in unreliable wire connections.

3. Pay attention to the rear row of the car after the car is turned off and the cherry cracks are broken. Because the exhaust pipe of the tail exhaust is very hot when using the Yuanqin car, and then if the tail exhaust is accidentally flushed when washing the car, then the exhaust pipe is violently cooled by external influences, which may cause the ceramic sensitive element of the oxygen sensor to burst, and then the oxygen sensor will "strike."

Millions of car purchase subsidies.

With the wide application of electronic control technology in automobiles, oxygen sensors are widely used in engine control systems. Oxygen sensors are very important for the combustion condition of a car's engine, so they are installed on the engine's exhaust pipe. There are two types of oxygen sensors:

zirconia and titanium dioxide. Zirconia oxygen sensors reflect the concentration of a combustible gas mixture through a change in voltage. Titanium dioxide sensors reflect changes in combustible mixtures through changes in resistance.

We all know that the theoretical air-fuel ratio of the engine is: 1, and the oxygen sensor is a feedback control system, which detects the oxygen concentration and air-fuel ratio in the exhaust gas by electronically controlling the vertical setting of the fuel injection loading and selling, and sends feedback signals to the computer. Zirconia oxygen sensors reflect changes in the concentration of combustible mixtures through voltage changes.

When the engine condition deteriorates, the electronic control system using the zirconia oxygen sensor cannot control the actual air-fuel ratio around the theoretical air-fuel ratio. The titanium dioxide oxygen sensor may control the actual air-fuel ratio around the theoretical air-fuel ratio. The working principle of the zirconia oxygen sensor is as follows:

Zirconia oxygen sensors are plated with a layer of platinum. Under the conditions of high temperature and platinum catalysis, CUHK uses the difference in oxygen concentration between the inner and outer sides of zirconia to produce a potential difference. The greater the concentration difference, the greater the potential difference.

Due to the high temperature and the catalytic action of platinum, the oxygen attached to the oxygen sensor is depleted, so a voltage difference is generated. The oxygen sensor is a key sensor for fuel metering because it controls the air-fuel ratio according to the voltage signal of the oxygen sensor to adjust the pulse width of the fuel injection. As a key component to control automobile exhaust emissions, reduce automobile environmental pollution, and improve the combustion quality of automobile engines, oxygen sensors have become an indispensable and important part of modern automobiles.

The function of the automotive oxygen sensor is to detect the oxygen contained in the gas (exhaust gas) discharged from the cylinder. The on-board computer controls the amount of air and fuel entering according to the oxygen content of the exhaust gas, so that the fuel can be fully burned without wasting and generating pollutants, and at the same time ensuring that the air does not enter too much and waste valuable cylinder volume.

The function of the automotive oxygen sensor: 1. Monitor the mixed gas at any time to keep the engine in the best mixed gas combustion condition; 2. Manipulating automobile exhaust emissions and reducing automobile air pollution; 3. Damage to the oxygen sensor will cause fuel consumption to increase and exhaust gas to exceed the standard. The automotive oxygen sensor is a crucial feedback sensor in the EFI engine control system, and it is a key component to control automobile exhaust emissions, reduce automobile air pollution, and improve the fuel combustion quality of automobile engine.

Oxygen sensors are mounted on the engine exhaust pipe.

Oxygen sensors can be divided into front and rear types, both of which are mounted on the exhaust pipe of the engine. The front of the three-way catalytic converter is a front oxygen sensor, which is used as a sensor to monitor the combustion status of the engine. The three-way catalytic converter is followed by the rear oxygen sensor, which is used to monitor the oxygen sensor after the three-way catalytic converter.