How To Clean A Vehicle's Oxygen Sensor

Posted on: 29 July 2017

A check engine light or poor gas mileage could mean your vehicle's oxygen sensor needs cleaning. The oxygen sensor on your vehicle controls the output of emissions, but they can get clogged from fluids. You will commonly find the oxygen sensor in the engine bay and it is close to the size of a spark plug. You should be able to clean the sensor yourself by following this guide:

Prepare to Clean the Sensor

You need the following supplies to clean the oxygen sensor:

  • work gloves
  • eye goggles
  • vehicle jack and jack stands
  • paper towels
  • soft brush
  • wrench set
  • lubricant
  • gasoline-resistant container
  • gasoline

Park the vehicle on a flat surface in a well-ventilated area with plenty of light. Ensure you park away from plants you don't want to get touched by chemicals. 

Shut off the ignition if the vehicle has been running, and wait for it to cool. Engage the parking brake, and elevate the front of the vehicle on a jack giving yourself enough room to crawl under the vehicle, and support the back wheels with jack stands.

Disconnect the Sensor

Look for the oxygen sensor, or refer to your manual for the exact location. Most vehicles have two sensors: one installed in the engine exhaust manifold and the other near the catalytic converter. Coat the sensors with lubricant, and let it stand several minutes to make them easier to remove.

Attempt to remove the sensors with the correct size wrench, and lay them on a paper towel. The sensor may seem stuck since they are seldom removed. If you have trouble removing them, add another coat of lubricant, then try to remove it again.

Clean the Sensors in Gasoline

Place the sensors in the bucket, and cover them with gasoline, then place a lid on the container. If possible, try to find a gas-resistant container with a strong lid at a hardware store. Otherwise, you will have to use a strong lid such a plywood or an old heavy pot.

Gently shake the container, so the gas can get in every part of the sensors, and leave it in a safe place overnight away from pets or kids. Ensure no one smokes or brings any open flame around the container, which could combust. After the sensors have soaked, scrub them gently with a soft brush, and use a paper towel to dry them.

Reinstall the sensors, lower the vehicle from the jacks, and start the engine. If the check engine light is still on, take the vehicle to an auto servicing shop.