How to Change the Oxygen Sensor on Toyota Cars

by Contributing Writer; Updated June 12, 2017

The oxygen sensor on your Toyota car regulates the fuel mixture that your car is burning. If there is not enough oxygen in the exhaust, your car is running too rich and burning too much fuel. A failing oxygen sensor can cause significant decreases in fuel mileage as well as poor idling. The oxygen sensor on your Toyota car is located under the car, near the crankshaft. Buy a replacement sensor from an auto parts store or a Toyota car dealer.

Under The Hood:

 How to Change the Oxygen Sensor on a 2007 RAV4

Air-Fuel Ratio Sensor –- Upstream Oxygen Sensor

Allow the vehicle to sit until the engine has cooled completely.

Open the hood and find the air-fuel ratio sensor on the exhaust manifold, which is the large exhaust component that bolts directly to the engine.

Trace the sensor’s wiring toward the driver’s side of the engine until you find the harness on the end of the wiring. Pull the wiring from any routing clips as you encounter them. Unplug the sensor’s harness from the RAV4’s wiring harness.

Remove the air-fuel ratio sensor from the exhaust manifold using a ratchet and oxygen sensor socket. Pull the sensor from the engine compartment.

Thread the air-fuel ratio sensor into the exhaust manifold by hand, then tighten the sensor to 32 foot-pounds, using a torque wrench and oxygen sensor socket.

Route the air-fuel sensor’s wiring back towards the RAV4’s wiring harness, pressing the wiring into its routing clips as you encounter them. Plug the sensor’s wiring harness into the RAV4’s harness.

Heated Oxygen Sensor –- Downstream Oxygen Sensor

Park the RAV4 on a flat surface and allow it to sit until it is completely cool. Kick wheel chocks under the rear of the rear wheels. Lift the front of the SUV with a floor jack and slide jack stands under the subframe. Lower the RAV4 onto the jack stands.

Trace the oxygen sensor’s wiring away from the sensor until you find the wiring harness, which connects to the RAV4’s wiring harness. Unplug the sensor’s wiring harness from the vehicle’s harness.

Remove the heated oxygen sensor from the exhaust pipe using a ratchet and oxygen sensor socket.

Thread the oxygen sensor into the exhaust pipe by hand, then torque it to 32 foot-pounds using a torque wrench and oxygen sensor socket.

Connect the heated oxygen sensor’s wiring harness to the RAV4’s wiring harness.

Lift the vehicle off the jack stands and remove the jack stands. Lower the RAV4 to the ground.

Items you will need

  • Ratchet

  • Oxygen sensor socket

  • Torque wrench

  • Wheel chocks

  • Floor jack

  • Jack stands

 How to Replace an Oxygen Sensor on a 2005 Toyota Camry

Raise the front of the car with a jack and secure it on a set of jack stands. Locate the oxygen sensor near the crankshaft at the base of the engine.

Disconnect the wiring harness from the oxygen sensor. The wiring harness should pull straight off. Remove the oxygen sensor using an oxygen sensor socket and a ratchet.

Insert the new oxygen sensor socket, starting it by hand to prevent damaging the sensor. Tighten it with the oxygen sensor socket and ratchet, then torque the sensor to 32 foot-pounds with a torque wrench.

Reattach the wiring harness to the oxygen sensor by pressing it straight into the connector. Raise the car to remove the jack stands. Lower the Camry to the ground.

Items you will need

  • Jack

  • Jack stands

  • Oxygen sensor socket

  • Ratchet

  • Torque wrench

 How to Replace an Oxygen Sensor on a Toyota Avalon

Locate the Avalon's two oxygen sensors on either side of the catalytic converter on the exhaust manifold. The Avalon's oxygen sensors look like a gold spark plug with a wire coming off the end.

Remove the Toyota Avalon's wiring harness from the end of the both oxygen sensors using your fingers. Do not damage the end of the Avalon's wiring harness.

Take out both of the Avalon's oxygen sensors using the oxygen sensor wrench.

Apply the anti-seize compound to the Avalon's two new oxygen sensors threads.

Install the Toyota Avalon's two new oxygen sensors using the oxygen sensor wrench. Re-attach the wiring harness to the Avalon's oxygen sensors using your fingers.

Items you will need

  • Oxygen sensor wrench

  • Anti-seize compound

 How to Replace the Oxygen Sensor on a Toyota Sienna

Raise the hood of your Sienna and locate the two sensors in the engine compartment. There is one in each exhaust manifold on either side of the engine. The third sensor is located under the van just downstream of the catalytic converter and can only be accessed from under the van.

Locate the wiring harness on the top of the O2 sensor and follow it back until you locate the connector where it joins the main wiring harness. Release the locking tab on the connector, then separate the two halves.

Install an O2 sensor socket on the sensor, then turn it counterclockwise with a ratchet until it is loose enough to remove. Discard the old sensor. Thread in a new one and then tighten the sensor with the O2 socket and ratchet.

Run the wiring harness to the connector on the vehicle's main wiring harness and push the two connectors together. Make sure the locking tab engages and the two connectors are secure.

Raise your Sienna with a jack and position a set of jack stands under the front suspension to support it. Slide under the vehicle, locate the O2 sensor right behind the catalytic converter, and repeat the same process you used under the hood to replace the other sensor if required.

Raise the Sienna off the jack stands with your jack, remove the stands and lower the van to the ground. Remove the jack from under the vehicle then close the hood.

Items you will need

  • O2 sensor socket

  • Ratchet

  • Jack

  • Jack stands

 How to Replace the Oxygen Sensor on a 2000 Toyota Corolla

Jack up the front of the Corolla using a floor jack underneath the front jack point of the Corolla just behind the radiator support.

Place a jack stand under each of the front pinch welds on the body of the vehicle under the front doors.

Lower the Corolla onto the jack stands.

Climb under the vehicle and locate the two oxygen sensors. One sensor will be in front of the catalytic converter towards the front of the vehicle. The other oxygen sensor will be behind the catalytic converter towards the middle of the vehicle. The sensors will look like plugs sticking out of the exhaust with wires coming out of the sensors.

Disconnect the electrical leads from the oxygen sensors by pushing down on the release tab on the sensor connector and pulling it off of the sensor.

Unbolt the sensors from the exhaust using a socket wrench and O2 sensor socket.

Thread and tighten the new sensors using an O2 sensor socket and socket wrench.

Reconnect the electrical connectors to the sensors.

Lower the Corolla to the ground using the floor jack.

Items you will need

  • Floor jack

  • Jack stands

  • Replacement O2 sensor

  • Socket wrench

  • O2 sensor socket

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