How to Install an Oxygen Sensor on a J30

An oxygen sensor is one of many sensors used by the computer for engine management. The oxygen sensor gives off a voltage when it comes into contact with oxygen within the exhaust system. The higher the voltage count the more oxygen and the opposite for lower concentrations. High oxygen content means a lean mixture or not enough fuel in the mixture - too little oxygen and the mixture is rich. The computer takes these readings and makes the appropriate adjustments to keep the mixture at an optimum 14.5 to 1. The oxygen sensor is one of the only sensors that will set a code stating that the signal is out of range in real time. Now this could mean that the sensor is bad or in most cases it is out of range due to a problem with the engine. Any kind of a problem like plugs, wires, vacuum leaks - and the list goes on - can cause a poor mixture and set the service soon light on with this code. It would do well to check the engine tune and the operation of the injectors and so on before condemning an oxygen sensor.

You will need the following items to complete this project:

Code scanner to find out which oxygen sensor is bad. Each car has a minimum of two and as many as four sensors.
7/8 open end wrench
½-inch drive oxygen sensor socket
½-inch drive ratchet
Floor jack
Jack stands

Install the code scanner into the OBD port located under the driver's side dash. It is usually made quite accessible. Turn the ignition key on with the engine off and press the read button on the scanner.

Record the code and cross-reference it with the code sheet that came with the scanner. The sensors are numbered such as B1S2 which means bank 1 sensor 2. There is a sensor in the front of each catalytic converter and one behind it to monitor what goes in and what comes out. Turn the key off.

Raise and support the car on jack stands. Disconnect the wiring harness connector for the sensor. Using the appropriate tool that will fit into the area on the oxygen sensor, remove the oxygen sensor.

Install some antiseize compound on the end of the threads of the new sensor so that it will not rust into the exhaust and come out at a later date. Install the sensor and tighten to about 20 foot pounds of torque. Connect the sensor harness connector.

Lower the vehicle and erase the code to turn the check engine light off. Turn the key on and push the erase button on the code scanner to erase the code.