How To Clean Oxygen Sensor Without Removing?


Increased emissions, loss of fuel efficiency, rotten egg or sulphur smell, engine hesitation or power surges, check engine light, and black smoke from the exhaust tailpipe are the common signs of a bad or dirty oxygen sensor. If you notice two or more of these signs, you have a bad or dirty O2 sensor that needs cleaning or replacement.

how to clean o2 sensor

The best way to clean an O2 sensor involves removing it first and then cleaning it using a solvent, petrol, blow touch, or electronic cleaner. But in this article, you will learn how to clean oxygen sensor without removing it and still get excellent results. Sit back and watch as I guide you through a no-fuss method to cleanse your oxygen sensor without removal.

What causes dirty O2 sensors?

Since the oxygen sensor is connected to the exhaust pipe, it can only get dirty as a result of other issues in the engine. Excessive blow-by in an older engine, too rich of a fuel mixture, and engine coolants being burnt in the combustion chamber due to internal coolant leaks are common causes of dirty O2 sensors. Other factors like age, wear, and faulty wiring or connectors can cause the oxygen sensor to fail.

All these can affect how your O2 sensor works—making it slower to respond to changes and give incorrect readings, ultimately leading to the sensor not working as effectively as it should over time.

Can O2 sensors be cleaned and reused?

It’s not whether can O2 sensors be cleaned and reused but whether cleaning will do any good. With this question, my answer is that I don’t recommend cleaning O2 sensors—replace them with a set of good ones. O2 sensors are sensitive and prone to be fragile. The caveat is that if the sensor is coated with carbon deposits due to a rich fuel mixture, fixing that issue will clear the carbon deposit on the oxygen sensor after covering a few hundred miles.

 Cleaning the sensor won’t do much. It will only remove the carbon buildup on its outer surface, while the carbon deposits inside will remain. Instead, find out why the sensor is covered in soot in the first place and fix it.

How to clean oxygen sensor without removing

As I said earlier, the best way to clean an oxygen sensor is to remove it before cleaning it with a solvent, petrol, glow touch, or electronic cleaning device. However, I will walk you through how to clean O2 sensors without going through the hustle of removing them.

Tools and Items Needed

  • Oxygen sensor cleaner
  • Hand gloves
  • O2 sensor wrench

Step 1: Remove the plastic engine cover

First, open the hood and remove the plastic engine cover by removing the bolts or clips holding it in place. If your car doesn’t have this plastic cover, skip to the next step.

Step 2: Find the O2 sensor

Cars with inline engines have two oxygen sensors located before and after the catalytic converter on the exhaust pipe. V layout engines have four sensors—two on each exhaust pipe.

Check the sensors and the wiring harness for physical damage. Ensure the connectors are correctly plugged. If you want to check the before and after effects, remove the oxygen sensors and snap them with your phone camera. Suppose you don’t want to; move on to the next step.

Step 3: Remove your engine vacuum hose

The next step is to locate and disconnect the engine vacuum hose connecting to the brake servo. Then, insert the cleaner straw into the hose and reconnect it.

Step 4: Turn on the engine

Start the car and let it idle for 5-10 minutes to allow the engine to reach its average operating temperature. Have someone depress the gas pedal and hold it at 2000 RPM. While the person keeps the engine at 2000 RPM, connect the O2 sensor cleaner to the other end of the spray and gently spray as the engine is running.

Step 5: Round up

Shut off the engine and disconnect the vacuum hose. Then, take off the cleaner spray and reconnect the vacuum hose properly.

If you took a picture of the oxygen sensor in step two, remove it again and take the after-effect picture. Compare the images and see the result you achieved. If not, disregard this and test-run the car for 15 to 20 minutes. This will help burn off the residues you cleaned from the sensor.

What is the best way to clean your O2 sensors?

Petrol is known for cleaning O2 sensors thoroughly. Still, the best way to clean those is to remove O2 sensors and then clean them with the best oxygen sensor cleaner commercially specified for cleaning those. Do not clean oxygen sensors with home remedies like household detergent or vinegar since they can damage the sensor.

Can you clean sensors with carb cleaner?

Cleaning the O2 sensor with a carb cleaner is a feasible way of removing carbon deposits. Carb and choke, WD-40, and gasoline are the best solutions to remove carbon deposits from oxygen sensors.

To clean using carb cleaner, spray it on the O2 sensor and let it sit for 5 to 10 minutes. Scrape off stubborn carbon deposits with a soft brush and respray the carb cleaner.

How often do you need to clean an oxygen sensor?

Cars that are not driven more may require cleaning the O2 sensors once a year. Meanwhile, the ones used for daily commutes require cleaning the sensor twice a year. However, O2 sensors only get dirty when there is too rich a fuel mixture or when coolant is burnt in the combustion chamber due to an internal leak. The only way to keep your engine purring for years without cleaning or replacing the oxygen sensor is to keep your engine in good condition.

Final words

Now, you know how to clean oxygen sensors without removing them. However, while this is the easiest method of cleaning oxygen sensors, you need to know that car manufacturers do not recommend it. Also, some experts opined that solvent or cleaner is not safe to go through your engine as it could cause damage to it.

Solomon Osuagwu

Osuagwu Solomon is a vetted auto mechanic with over ten years of experience in the garage and five years of experience as a service writer. He prides himself in writing accurate information on professional repair guides, DIY repair guides, buyer’s guides, comparisons, and car reviews. If he’s not in his repair garage, he’s writing automotive blogs to help car owners and fellow mechanics to troubleshoot and proffer solutions to several car problems.

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