How to Clean a Car's Oxygen Sensor

Over time, the oxygen sensor of a car’s exhaust system can accumulate too much dirt, soot and other contaminants. When this happens, the efficiency of the oxygen sensor as well as that of the exhaust system may decrease. Likewise, the combustion of gasoline in your car’s engine may be affected. To avoid such problems, it is necessary to keep the sensor clean and free from contaminants.

Tools and Materials

  • Safety gear (gloves and goggles)
  • Paper towels
  • Wrench
  • Gas safe container (preferably with lid)
  • WD 40 
  • Gas

Step 1: Prepare the Car and Work Area

Take and park your car in an area where you can work undisturbed. The work area must be large enough for you to move around. If necessary, install proper lighting and ventilation on the area before you begin the process of changing your car's oxygen sensor.

Step 2: Wear Safety Gear

Put on the gloves and goggles and other available safety gear. These things will help keep you protected from untoward accidents that may happen while you are in the process of cleaning the sensor.  

Step 3: Remove the Oxygen Sensor

Put your car in an elevated position. You can use the jack to raise the car a bit. Once the car is held into position, slowly get under the vehicle and locate the sensors. Spray the oxygen sensors with the WD 40 for lubrication, and then use the wrench to unplug and remove the sensor that needs cleaning from the engine.

Step 4:   Submerge the Sensor in Gas

Get the gas-safe container with cap or lid. The container must be air-tight and must not have any leak. Place the sensor inside it. Put gas inside the container and make sure that the sensor is completely submerged. Put the cap or lid on, making sure that no gas can escape.

Step 5: Swirl and Rotate

Swirl and rotate the container in a gentle and careful manner. This will make the gas swirl inside. The process can also make the gas penetrate the different parts of the sensor, thereby washing away all dirt and soot that have accumulated into the sensor's cracks.

Step 5: Leave to Rest   

Leave the container in a safe and cool, dry place to rest overnight. This process will make the gas react more with the contaminants that have accumulated in the sensor.

Step 6: Re-agitate the Gas and Mixture

Rotate and swirl the container again in the morning. This will re-agitate the gas and mixture inside and will help make sure that dirt has been fully washed away from the sensor.

Step 7: Dry the Sensor

Wear gloves again and remove the sensor from the container. Wipe with paper towels to dry.

Step 8: Reinstall 

Put the sensor back into its position in your car's engine. Make sure that it is installed tightly and securely. Use a wrench to tighten its bolts.