Car Oxygen Sensor Error: Cause, Condition, How to Handle

Car Oxygen Sensor

Oxygen sensor (oxygen sensor) is an important device in cars, helping to measure the amount of harmful gases emitted from the engine and adjust the fuel ratio to minimize emissions. This part plays a very important role in maintaining the performance and fuel economy of the engine.

So what if the oxygen sensor has a problem? The ratio of fuel and air when burning will not reach the ideal level, leading to fuel consumption and creating an unpleasant smell.

If the Check Engine light is on and you suspect that your car's oxygen sensor is having a problem, let's find out the cause, condition, and effective treatment in this article.

Car Oxygen Sensor
Car Oxygen Sensor

How Do Oxygen Sensors Work?

The task of the oxygen sensor is to measure the amount of residual oxygen in the car engine exhaust and transmit a signal to the ECU control system.

When the amount of oxygen in the exhaust gas decreases, the output voltage of the sensor will decrease. Conversely, as the amount of oxygen increases, the output voltage of the sensor will increase. From these parameters, the ECU system will calculate and adjust the ratio of fuel and intake air to make the engine work most efficiently.

There are two common types of oxygen sensors: Heated Sensor (Oxygen Narrowband) and Non-Heat Sensor (Oxygen Sensor).

Structure of Oxygen Sensor
Structure of Oxygen Sensor

Each type will have a different structure, but they all often encounter the following errors:

  • Sensor is dirty.
  • The sensor is bent, wire broken, broken.
  • Dead sensor.

Signs That The Oxygen Sensor Is Defective

When the oxygen sensor fails, it will lead to many different problems in the car. Here are the signs that the oxygen sensor is faulty:

The car consumes gas

When the oxygen sensor is faulty, it will not transmit the signal correctly. At this time, the ECU system cannot properly analyze the amount of fuel injected, leading to a lot of fuel injection, causing "excess fuel".

If not rectified soon, fuel consumption will increase.

Engine not working properly

A faulty oxygen sensor can also cause the engine to run unstable, reduce performance, cause vibrations, make it difficult to start or slow down the vehicle.

Unpleasant smell of gasoline

A distinct smell of raw gasoline is also a sign that your car's oxygen sensor is having problems. The reason is that too much fuel is injected into the combustion chamber while the amount of oxygen is less, causing excess gasoline. This excess gasoline will be expelled through the exhaust pipe, causing an unpleasant odor.

Check Engine light comes on

If the Oxygen Sensor is Faulty, the Check Engine Light is On
If the Oxygen Sensor is Faulty, the Check Engine Light is On

The Check Engine light is on when the engine or related components have a fault. Therefore, if this light is on, it is possible that the oxygen sensor is faulty.

If you see any of these signs, check them out right away to make sure your trip is safe.

How to Test the Oxygen Sensor

For a simple self-test of the oxygen sensor at home, you can use a voltmeter. Usage is as follows:

Step 1: Connect the negative (-) lead to the chassis or body, the positive (+) to the output of the oxygen sensor. When the engine is hot, you unlock but do not start the engine. If The voltage from the sensor at 0.4 - 0.45 V is normal.

  • Step 2: Disassemble the oxygen sensor connector to connect to the voltmeter, start the car and increase or decrease the throttle. If the voltage fluctuates in the range of 0.5 V, the oxygen sensor is still normal, beyond this level, it may be a problem.
How to Test the Oxygen Sensor
How to Test the Oxygen Sensor

If you are unsure of how to check the oxygen sensor, it is best to take your vehicle to a reputable garage to have it identified and repaired promptly.

Oxygen Sensor Cleaning Instructions

Cleaning the oxygen sensor periodically will help it function properly and prolong its life. If you want to test and clean the oxygen sensor yourself at home, you can follow these steps:

Step 1: Prepare tools:

It is necessary to prepare tools such as glasses, gloves, car jacks, containers, soft brushes, specialized cleaning solutions, etc.

Step 2: Turn off the engine and locate the sensor:

Before starting to clean the oxygen sensor, you should turn off the engine and wait for the engine to cool completely. Use the car jack and locate the oxygen sensor.

Step 3: Remove dirt:

Use a soft brush to remove dirt and dust on the surface of the oxygen sensor so as not to cause scratches.

Step 4: Sanitizing spray:

Use a specialized solution to clean the oxygen sensor and let it sit for 10 minutes. You can buy products at auto parts stores or auto repair garages.

Step 5: Wipe clean with a soft cloth:

Use a soft cloth to clean the surface of the oxygen sensor. If you feel that the oxygen sensor surface is not completely clean, you can repeat the cleaning step with brush and spray.

Step 6: Check the status of the sensor again.

Use a voltmeter to check sensor operation. If the sensor has a problem, you can take it to the garage to have it checked, repaired or replaced.

Above is the information you need to know about the oxygen sensor: causes, conditions and treatment. Hope the article will be useful to you. For any questions about vehicle conditions, car repair and maintenance services, you can contact Thanh Phong Auto for expert advice!

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