How to replace the oxygen sensor — Toyota Camry 2020

Tools you'll need

• Oxygen sensor socket (22 mm)
• Ratchet
• Extension bar
• Torque wrench
• Penetrating oil

Parts you'll need

• New upstream oxygen sensor (Denso or OEM equivalent, Bank 1 Sensor 1)
• Anti-seize (usually already applied to the new sensor threads)

Steps

1. Let the exhaust cool to warm, not hotPark on a flat surface, set the parking brake, and open the hood. Let the engine cool until the exhaust manifold is warm to the touch, not hot. A slightly warm sensor comes out easier than a stone-cold one.
2. Locate the upstream sensor and unplug itFind the upstream oxygen sensor screwed into the exhaust manifold at the front of the engine. It has a wire running from its top to a plug on the wiring harness. Follow the wire to the plug and unplug it.
   Tip: The upstream sensor is the one before the catalytic converter. The downstream sensor sits after it, further down the exhaust.
3. Soak the threads with penetrating oilSpray penetrating oil around the base of the sensor where it threads into the manifold and let it soak for about 10 minutes.
4. Unscrew the old sensorSlide an oxygen sensor socket over the sensor and its wire, attach a ratchet, and turn counterclockwise to unscrew it. If it is seized, work it back and forth a little at a time instead of forcing it in one pull.
   Tip: An oxygen sensor socket has a slot for the wire. A regular deep socket will not fit over it.
5. Compare the new sensor and check the anti-seizeCompare the old and new sensors to confirm the plug and thread match. Check that the new sensor threads already have anti-seize on them, and add a thin coat if they do not. Keep the anti-seize off the sensor tip.
6. Thread the new sensor in by hand, then torque itThread the new sensor in by hand until it seats, so you do not cross-thread it. Then tighten it with the oxygen sensor socket to about 33 ft-lb.
7. Reconnect the plug and route the wire safelyRoute the new sensor wire the same way the old one ran and plug the connector back in until it clicks. Make sure the wire does not touch the hot exhaust or any moving part.
8. Start the engine and confirm the light stays offStart the engine and let it idle. The check engine light may stay on until the computer runs its own test, which can take a few drive cycles. If the light comes back after a few days of normal driving, have the codes read again to confirm the sensor fixed the problem.
   Tip: You can clear the old code with a scan tool, but the light will also clear itself after a few good drive cycles if the repair worked.

Safety first

Let the exhaust cool before you work on it. A hot exhaust manifold can burn you badly. Do not drop the new sensor or touch its tip, and do not use silicone sealant near it. If you are not confident, have a qualified technician do this job.