How to Replace an O2 Sensor on a 1996 Nissan Maxima

The 3.0-liter V-6 engine of the 1996 Nissan Maxima contains three oxygen sensors in the exhaust system. There are two upstream sensors in the front pipe just below the manifold flanges, and theres a third sensor down after the catalytic converter. Auto parts stores can determine which sensor has failed by reading the "check engine light" code the sensor has tripped. Most will perform this service for free in order to sell the parts to the customer.

Instructions

1

Apply the parking brake of the 1996 Nissan Maxima.

2

Hoist the front of the vehicle on one side with the car jack high enough to place a jack stand under the front frame rail. Repeat this for the other front side so the entire front axle of the car is elevated.

3

Put on the safety glasses. Locate the sensor being replaced by crawling under the vehicle. One sensor is located in the drivers side front pipe up near the manifold, another is in the shorter pipe (closer to the firewall) on the passengers side front pipe assembly, and the downstream sensor is located after the catalytic converter near the center of the undercarriage.

4

Disconnect the plug of the oxygen sensor from the plug of the harness.

5

Place the wire of the sensor through the opening of the 22-mm box-end wrench or in the slot of the O2 sensor tool. Place the wrench or tool onto the hex-head of the sensor.

6

Turn the wrench or tool (with a ratchet) to the left to remove it from the O2 sensor port. The sensors only have four to five threads, so once loosened, the sensor will quickly come out of the port.

7

Thread the replacement sensor into the port by hand. Tighten it with the wrench or tool and ratchet. Be caul not to overtighten the sensor. The threads are delicate and can be easily stripped. Tighten it snug only.

8

Connect the plug of the replacement sensor to the harness plug.

9

Collect the tools and other material from under the Maxima before lowering it to the ground.