How to Replace O2 Oxygen Sensor 02-03 Nissan Altima
Difficulty: Beginner · About 20 min · Nissan Altima
Replace an oxygen sensor on a Nissan Altima by unplugging its harness, threading the new sensor into the exhaust bung, and checking for warning codes.
Tools you will need
- O2 Sensor Socket
- 7/8 Inch Socket
- Ratchet
- Flat Blade Screwdriver
Parts and supplies
- Correct upstream or downstream oxygen sensor
Steps
Disconnect the sensor
Let the exhaust cool fully, locate the sensor being replaced, and release its electrical connector without pulling on the wiring.
Remove the old sensor
Use an oxygen sensor socket to loosen the sensor from the exhaust bung. If the sensor is seized, apply suitable penetrant and allow it to work before trying again.
Install the replacement sensor
Check the new sensor threads and seal, then thread it into the bung by hand to avoid cross-threading. Tighten to the sensor or vehicle specification and reconnect the harness.
Check the repair
Route the wire away from hot exhaust parts and moving components. Start the engine, confirm there are no exhaust leaks, and scan for codes if the warning light persists.
Check your vehicle’s repair manual for exact specifications and fit.