All You Should Know About the O2 Sensor After Oil Change

Are you wondering if there may be a problem with your O2 sensor after oil change?

Your vehicle needs an oil change as part of regular maintenance. But there are some people who wonder what risk this may put to their O2 sensor. Is there a correlation at all?

Today, we will discuss how your O2 sensor functions and the link between getting an oil change and this sensor. Let’s get started.

o2 sensor after oil change

O2 Sensor After Oil Change Facts

First of all, let us talk about your O2 sensor. Also known as an oxygen sensor, this component measures how much oxygen is present in your exhaust. This may seem such a very simple task. Yet, your O2 sensor performs an important job. In fact, it is responsible for maintaining a balance between your fuel and air to ensure an optimal emission.

With this in mind, it is important to know why exactly it can fail and the necessity of replacing this component once failure happens.

Now, your oxygen sensor is found throughout your exhaust system. There are usually two of these – one is in front of your catalytic converter while the other is downstream from your catalytic converter. For your pre-cat sensor, it helps to regulate fuel supply and the downstream one measures how efficient your catalytic converter is.

When it comes to O2 sensors, these may either be a wide band or a narrow band sensor. The sensing component is located in the sensor and secured in a steel-material housing. If your exhaust gas mixture has very little oxygen and is very rich, the ECU gets a signal from the O2 sensor. This helps to reduce how much fuel gets into your cylinder.

On the other hand, a lean gas mixture causes the O2 sensor to send a signal to notify the need to increase fuel used by your engine. When there is too much fuel, this leads to carbon monoxide and hydrocarbon production increase. But if it is too little, this leads to a production of nitrogen-oxide pollutants.

This is why your sensor is important in maintaining the right mixture. In the case of a wide-band O2 sensor, this comes with an extra O2 pumping cell that regulates how much oxygen is in the sensing element. Therefore, the air-fuel ratio is much wider.

It is important to note that O2 sensors may fail once there is contamination in them. For example, the contamination may include fuel mixture that is very rich. Or it could also be an oil blow-by issue in the case of an older engine. Thus, engine coolant becomes burnt in your combustion chamber when an engine gasket leak occurs. 

Since the O2 sensor is exposed in very high temperatures, it may be susceptible to wear and tear. All of these factors impact the function and integrity of the O2 sensor. This is why as time passes by, the sensor’s performance becomes less efficient. 

O2 Sensor Failure Symptoms

With all these things in mind, it helps to know what the common signs are for an O2 sensor failure. Typically, once it fails, your vehicle’s computer becomes unable to sense the right fuel-air ratio. This is why it becomes more and more inaccurate. 

A few symptoms may occur such as the check engine light being illuminated. But there may also be other causes why the check engine light turns on. So, it is important to know for sure why it happens.

Moreover, a reduction in your fuel economy may mean a problem with your O2 sensor. Hence, fuel usage becomes higher and the fuel economy goes down. 

Another symptom is misfiring or rough engine idling. Since your O2 sensor output is responsible for controlling the engine timing, once it fails, your vehicle tends to run roughly and can misfire. Your engine performance becomes poorer, and you may need to have your O2 sensor replaced.

Now, it is important to note that troubleshooting your O2 sensor requires certain steps and techniques. First, you need to read the fault codes showing up using your diagnostic tool. Several fault codes may appear, so it is good to know what causes these issues.

It is also important to check your heater’s power supply. It is common for the wires to have a similar color. Check for dirt or damage to the electrical connector and be sure there are no leaks in your fuel injectors and exhaust manifold. Inspect your ignition component’s condition as these may also be impacted by your faulty sensor.

Do you see if your O2 sensor is still reading correctly? You can confirm this by checking your gas emission analyser. Using an oscilloscope, you can check your signal at idle and when your engine speed is at 2500 RPM. You may also want to use live data that will check the signal if you have a difficult time accessing your sensor wiring. 

Inspect for any signs of damage to the probe element’s protective tube. If you see contamination and wear, this component’s efficiency may be compromised.

Additional Points To Consider

There are a few fault codes to note if your oxygen sensor is acting up. These include the following:

P0175 – The system (bank 2) is too rich

P0135 – This refers to the O2 sensor in front of your first catalytic convertor

P0713 – There is a fuel trim malfunction in the bank 2

P0162 – Your O2 sensor circuit is malfunctioning (sensor 3, bank 2)

P0171 – The system (bank 1) is too lean

Read More: Burning Oil Smell Through Vents: 5 Common Causes & Fix

Bottom Line

There are many signs to note if you are having issues with your O2 sensor. But it is important to keep in mind that prior to replacing it, you need to first diagnose the issue appropriately. Using your diagnostic tool, read the error code that shows up. This way, you can get to the root of the problem and use the right method that will produce a definitive and favorable result.

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