# Write-up on replacing the o2 Sensor on a 2000 Maxima



## techtalk (Jun 8, 2011)

Hey fellow Nissan fans!

A customer bought in their 2000 Maxima yesterday and complained about a rich fuel smell and loss of acceleration when they were driving so I immediately knew that the o2 sensor may have taken a dive. Sure enough the engine pulled the code indicating that the o2 sensor was bad. If anyone needs a simple write-up on the procedure for replacing the o2 sensor in your Maxima then here it is:

**REQUIRED TOOLS AND PARTS**
Floor jack (can be bought at Autozone)
Jack stands 
Replacement O2 sensor (I bought a cheap OEM one from Nissan Maxima Oxygen Sensor)
Socket wrench
Socket set


1) Jack up the front of the car using a floor jack under the front jack point behind the radiator.

2) Place jack stands under the front supports underneath the door.

3) Lower the vehicle onto the jack stands.

4) Climb under the vehicle and disconnect the electrical connector from the oxygen sensor.

5) Unbolt the oxygen sensor from the exhaust using a socket wrench and O2 sensor socket to remove the sensor.

6) Bolt in the new sensor using the socket wrench and O2 sensor socket.

7) Reconnect the electrical connector to the oxygen sensor.

8) Lower the Maxima to the ground.

9) You're done!


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## smj999smj (Jan 1, 2006)

You forgot to mention to make sure one is replacing the correct O2 sensor, as most late model cars have three or four. Nothing worse than installing a brand new sensor and finding out you replaced the wrong one! I know it would sound like common sense, but I've seen it done!


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## Pilm (Nov 21, 2011)

Might want to pull the negative terminal on the battery beforehand, better safe than sorry. If you have trouble removing the sensor, try PB Blaster, works great. Finally, be sure to use anti seize if not already on the threads of the new sensor.


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## NissMax (Mar 22, 2012)

This is a good write up.

I only have one concern. I just got the codes po139 and po138. And base on my reasearch, i need to replace my (white cap) oxygen sensor. I havent looked under the car to see where that is just yet, but how do i tell the advanced auto parts/autozone/carquest exactly what sensor i am looking for? Is there a part number of a name for that sensor?

Also, please help me out and confirm that this is my problem based on the codes..

Po139- o2 sensor CKT slow response (bank 1 sensor 2)
Po138- o2 sensor circuit high volts (bank 1 sensor 2)

Ps. I threw in a half of can of seafoam about 3 days ago into the gas tank, i refilled it up twice with gas since then. But i still think seafoam is to blame for this issue. The car has 77k miles. 2000 maxima gxe. Auto.


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