Can I replace an oxygen sensor myself?

The procedure to replace an oxygen sensor on many vehicles is not an extremely complicated one. That said, it is not always easy. First of all, a vehicle usually needs to be safely lifted and supported off of the ground for access to an oxygen sensor. Then there is the difficulty accurately diagnosing which sensor needs to be replaced (something that requires a diagnostic scan tool) and determining where that specific sensor is located. Dislodging the sensor from its mounting location is also tricky; an oxygen sensor is often stuck in place and too often breaks before loosening up.

What happens if an oxygen sensor is not replaced?

If an oxygen sensor fails and is not replaced, one thing that will happen is that your engine’s computer will not be able to accurately set the air/fuel mixture for combustion. Poor fuel economy and higher emissions will result. Damage to the catalytic converter is also possible - and costly. And your vehicle will probably not pass an emissions test.

What causes oxygen sensor failure?

An oxygen sensor usually goes bad because it becomes contaminated with a buildup of combustion byproducts, such as oil and soot. Sometimes, oxygen sensors get gummed up due to the use of cheap fuel. Even engine coolant that leaks into the combustion chamber through a faulty seal can also cause contamination.