How do you change the 02 sensor in a 2001 Toyota 4Runner?

To change the O2 sensor in a 2001 Toyota 4Runner, first, ensure the vehicle is cool and disconnect the negative battery terminal. Locate the O2 sensor, typically found on the exhaust pipe or manifold, and use a wrench or O2 sensor socket to unscrew it. Apply anti-seize compound to the threads of the new sensor, install it by hand, and then tighten it securely. Finally, reconnect the battery and clear any diagnostic trouble codes if necessary.