Does your car have a dirty O2 sensor? Did you notice any engine hesitation, bad fuel economy, a check engine light, or even a rotten smell from the tailpipe? Those are the usual symptoms when an O2 sensor is dirty.
When an O2 sensor gets dirty, it is most likely that there is some other problem like bad injector, or bad spark plugs.
I once had these symptoms because my O2 sensor was dirty. A took my car to the mechanic shop and I got an estimate of $300 for cleaning a dirty O2 sensor. However, I didn’t want to spend money on a mechanic to have it cleaned. It was way out of my budget for something that I thought I could easily do.
So, I went back home and spent some time researching how to clean the O2 sensor without removing it and was able to perform this task on my own. Here is how to clean your O2 sensor without removing it:
How To Clean O2 Sensor Without Removing It
The O2 sensor plays a big part in the engine operation. A dirty O2 sensor can cause black smoke from the tailpipe, engine hesitation, bad fuel economy, sulfur smell, and a check engine light. You shouldn’t drive your car with a dirty O2 sensor.
1. Gather the required cleaning and safety material
Before you start cleaning your O2 sensor without removing it, you need to gather the required cleaning and safety material. For cleaning the O2 sensor, I use a carb cleaner that I order from amazon.com. This carb cleaner will remove any deposits that might have built upon the O2 sensor.
However, since the carb cleaner spray is corrosive, it can cause damage to your skin. That’s why I always use gloves that I order from amazon.com. It doesn’t matter if you are working five minutes or five hours on your car, always wear the necessary protection.
2. Remove the engine plastic cover
You will need to gain access to the O2 sensor and the vacuum hose. In order to do that, you will need to remove the plastic cover of the engine. Not all vehicles have a plastic cover. If your car doesn’t have one, good. If your car has one, it will be usually secured with clips. Disconnect any clips or screws and safely store the engine plastic cover.
3. Locate the O2 sensor
The location of the O2 sensor will be different on different cars. However, the O2 sensor has the same look. You can find the location of your O2 sensor by reading the owner’s manual. The reason why we are locating the O2 sensor is just to visually inspect it.
The O2 sensor has wiring on one end that could be damaged and needs replacing. Inspect the wiring by disconnecting the wire harness and visually look for any cracks or damages. If everything is alright, reconnect the wiring. Then, check the O2 sensor without removing it. Just look for any cracks or visible damages.
4. Locate and remove the vacuum hose
There are many vacuum hoses inside the engine bay. The vacuum hoses have a mission to maintain pressure within the engine. The vacuum hose that we are going to need is located on the back of the engine.
Remove the clamp that is securing the vacuum hose and insert the carb cleaner straw. Then, reattach the vacuum hose and the carb cleaner straw back on. This vacuum hose leads exactly to the O2 sensor and by spraying the carb cleaner, you are going to clean the O2 sensor without removing it.
5. Start the engine
To clean your O2 sensor without removing it, you will need to start your engine and keep it running until it reaches the correct operating temperature. At this point, the engine will be hot and you will have to be careful when working on a hot engine.
Once the engine reaches the optimal operating temperature, rev it to 1000-1500 RPMs. Make sure that you are performing this either in a well-ventilated garage or outdoors.
6. Spray the carb cleaner
While one person revs the engine at 1000-1500 RPMs, you should spray the carb cleaner into the vacuum hose. Again, be careful because the engine is hot at this point. Depending on how dirty your O2 sensor is, you should spray at least half the carb cleaner can. Remember to use short sprays so you don’t flood the engine.
7. Reconnect the vacuum hose
Once you finish spraying the carb cleaner into the vacuum hose, remove the carb cleaner straw and reconnect the vacuum hose with a clamp. Make sure that the vacuum line is secured as you don’t want any air to get inside.
8. Take your car on a test drive
If you have followed each of the steps, at this point you should have a clean O2 sensor. You should take your car on a test drive and rev it above 2000-2500 RPMs just to make sure that there is no debris left in the vacuum lines. Then, when you come back, you can scan your vehicle with an OBD scanner that you can order from amazon.com.
The Best O2 Sensor Cleaner
There are a lot of O2 sensor cleaners out there, but I have used the CRC mass airflow sensor cleaner many times and I am very satisfied with this product. I used to have a ’92 Toyota that had a dirty O2 sensor. A friend of mine suggested I get this O2 sensor cleaner and I got it from amazon.com.
I only used half of the carb cleaner and managed to clean a very dirty O2 sensor. My check engine light was on for a long time. After I cleaned my O2 sensor with this carb cleaner, the check engine light turned off and hasn’t come on for the past year.