Skip to Main Content

Your Car's Oxygen Sensor - What is it? Why is it important?

The oxygen sensor is an electronic device used to measure the proportional amount of oxygen in a liquid or gas. All cars manufactured after 1980 have at least one of these crucial pieces of equipment, located in the emissions control system. A correctly functioning O2 sensor sends data to the management computer located inside the car's engine. This ensures the engine is running at its best as well as helping to keep your emissions in check as well as alert you when your car's emissions become too excessive. Some states have vehicle inspection programs to help regulate emissions and the use of the check engine light and O2 light will alert officials to excessive emissions. Because of this, if one or more of your oxygen sensors is faulty during an emissions inspection, your car will most likely not pass the inspection. 
Schedule Service
What does is mean when the check engine light turns on
When should an Oxygen Sensor be replaced?

Usually, Oxygen sensors are not among the items that need to be replaced regularly like an oil or air filter. Typically they only need to be replaced when they fail. O2 sensors are a critical component of the fuel and emissions systems due to their role in monitoring the amount of oxygen in the exhaust and transmitting that information to the engine's computer. The computer then adjusts the air-to-fuel ratio accordingly. Should an oxygen sensor actually fail, the computer will be unable to accurately set the air-fuel ratio which can lower the fuel economy of your vehicle, raise your car's emissions, and damage other components like your catalytic converter due to overheating!

Unfortunately, vehicles wont show a check-engine light when an O2 sensor fails by itself, so you will need to rely on other vital signs to inform you that an oxygen sensor has failed. That's why its important to bring your vehicle in for regular maintenance by a skilled team of technicians like the ones found at

Signs your Vehicle's Oxygen Sensor needs to be replaced

An illuminated check-engine like could be one sign of a faulty O2 sensor or of a more serious issue like with your vehicle's catalytic converter, or even a mild issue like a loose gas cap. As a result further investigation as to the cause is always required. Thankfully the technicians at can easily read what triggered the check-engine light as a part of routine maintenance. Some other signs toy may need a new oxygen sensor can include:

  • Rough Idling
  • Misfiring Spark Plugs
  • A Lack of Power
  • Stalling 
  • Significant Increase in Fuel Consumption 
While these issues can also be the results of different problems, the EPA says replacing a bad 02 sensor can improve fuel economy by as much as 40 percent, so that is definitely a reason to check it if your car starts to consume more gas. As stated above; failing an emissions test can also be due to a faulty oxygen sensor. A new oxygen sensor can range from $100 to $300 (not including labor) based on the model and the type of vehicle you drive. That said; its a price worth spending given the other issues a failing O2 sensor can cause for your vehicle. 

    Maintenance & Service

    Our  service center near  is staffed with expert technicians who can handle your maintenance needs. 

    Schedule Service - Air Conditioner Repair - Check Engine Light - Seasonal Maintenance - Catalytic Converter Replacement - Transmission Repair - Engine Sputtering - Brake Pad Squeaking - Oxygen Sensor - Oil Change - Shop Tires - Coolant Leaks