The oxygen (or O2) sensor on your Toyota helps balance the engine's fuel-to-air ratio. A faulty O2 sensor can cause your engine light to come on. It might also prevent the vehicle from starting. Your Toyota is equipped with two O2 sensors. They are located underneath the vehicle on the exhaust pipe, with one on either side of the catalytic converter.
Set the emergency brake.
Jack up the front end of your Toyota. Put the jack stands in place.
Slide under the vehicle with the socket set and locate the O2 sensor you will be replacing. Sensor 1 is located on the exhaust pipe, on the left hand side of the catalytic converter. Sensor 2 is located on the right hand side of the catalytic converter closest to the vehicle's rear end.
Loosen the two mounting bolts that hold the sensor to the exhaust pipe with your socket set.
Unplug the sensor from its socket by squeezing in the two safety tabs on the sides of the socket and pulling the sensor free.
Plug in the new O2 sensor. Re-mount it to the exhaust pipe with the mounting bolts.
Remove the jack stands and lower your Toyota.
