An O2 sensor senses the chargeless O2 in the exhaust method. Raise and support the vehicle on jack stands. Disconnect the electrical connector on the oxygen sensor.2. Many things, including but not limited to a bad plug, wire or coil--and if present, the distributor cap can affect the oxygen sensor signal.
Instructions
1. Check for intake leaks prior to replacing an oxygen sensor---intake manifold leaks will cause the oxygen sensor to set a code. It creates a low, fixed varying voltage that is used by the pc to analyse the description of the fuel mixture. The computer takes this information and is continuously modifying the on-time of the injectors for the optimum 14.5:1 air-fuel mixture. This is the best fuel mixture to keep the cylinder heads cool, prevent detonation and for the most efficient emission controls. When the check engine light illuminates and sets a code for the oxygen sensor, it does not necessarily mean that the oxygen sensor is at fault.
Remove the oxygen sensor using the 7/8 wrench or the socket, whichever fits in the particular spot.
3. Install the new oxygen sensor by lubricating the threads with some antiseize compound or equivalent. Tighten the sensor down to the point that is tight, but do not over tighten. There is not a necessity to torque down on the sensor. It will not come out and too much torque will only distort the sensor causing failure.
4. Reconnect the electrical connector. Remove the car from the jack stands.