Easily compare & book over 1,600 quality reviewed mechanics Australia-wideGet Instant Quotes
How Much does a Oxygen Sensor Replacement Cost?
Your car’s emission system keeps your tailpipe emissions as clean as possible, and your oxygen sensors are the main component to meter and adjust emissions levels.
In its normal course of duty, the oxygen sensor will fail or burn out eventually and require replacement.
Normally, oxygen sensors will need to be replaced approximately every 150,000 to 200,000km, although failure can often occur beforehand.
The cost to replace an oxygen sensor is typically around $225 to $500, although some oxygen sensor replacements can be much more.
In many cars, more than one oxygen sensor – an upstream and downstream O2 sensor – are used, and are commonly replaced at the same time.
Oxygen Sensor Replacement
What is a Oxygen Sensor Replacement?
An oxygen sensor is an electrical component that analyses exhaust gas for the presence of oxygen.
On most modern vehicles, there is typically an oxygen sensor before the catalytic converter and another after, determining its operating efficiency.
Most oxygen sensors must reach 600 degrees before they produce a reading, thus a small heating element is used in the sensor to bring it up to temperature quickly.
The oxygen sensor creates voltage based on the amount of oxygen in the exhaust gas.
High voltage indicates a rich fuel mixture while low voltage indicates a lean air/fuel mixture.
When the electrical contacts in the sensor corrode or the heater fails to operate, the oxygen sensor does not produce an accurate reading.
This will cause the Check Engine light to illuminate, and the O2 sensor will need to be replaced.
Symptoms You Require Oxygen Sensor Replacement
- Check Engine light is on
- Fuel consumption is excessive
- The engine runs rough
- A rich smell from the exhaust
How is the Oxygen Sensor replaced?
- The technician performs a computer diagnostic test to isolate the failed sensor
- The car is raised and access cleared to the exhaust system
- The old oxygen sensor wiring is disconnected and the sensor unthreaded from its port
- The new sensor is fitted and the wiring connected
- The car is lowered and the engine started
- The technician performs a diagnostic test to ensure the oxygen sensor is reading correctly
Tips to Remember
- Other conditions can mimic oxygen sensor failure such as contaminated fuel and EGR system problems.
- The oxygen sensor must always be replaced with the exact same sensor for proper operation.
- Cars manufactured before 1996 may only have one oxygen sensor.
How Important is Oxygen Sensor Replacement?
Having a failed oxygen sensor replaced will give you peace of mind that your car is running properly as the Check Engine light will no longer be on for that reason.
Operating your car with a faulty or burnt-out oxygen sensor can increase fuel consumption and produce more harmful emissions, contributing to smog.
If you’ve read this far, you obviously care about your car. A lot. So next time you need a service, repair or inspection, visit AutoGuru.com.au.
We let you search and book from over 1600 qualified mechanics, who eat car troubles for breakfast.