How to Replace a car Oxygen Sensor
The oxygen sensor for you car is designed to monitor the amount of oxygen is in the exhaust system at any given second. This is done by using an active chemical that when heated can act as a low voltage generator. Follow this link to seehow an oxygen sensor works. There are many conditions that can cause an oxygen sensor to miss-behave even though there is nothing wrong with the sensor, to be sure the sensor is the problem by visiting how to test an oxygen sensor. Old cars will have just one sensor in the exhaust system while newer cars will have as many as four sensors. The reason behind the multi-sensor cars is control and monitoring capabilities. A multi-sensor system will be able to monitor the exhaust gasses before and after thecatalytic converter.
Most sensors are designed with a heater element to aid the sensors functionality when cold. Failure of this element is common and will warrant sensor replacement. When a sensor or the heating element inside the sensor fails it will trigger a check engine orservice engine soon light in most cases. If this occurs connect a scanner tool to your vehicle to access the diagnostic trouble code to help pin point the failed sensor. Once you have determined which oxygen sensor has failed, or you would like to simply replace the sensor to test for a problem you will need to follow these instructions to replace it. When a O2 sensor fails it can cause the engine torun lean or rich depending on the failure.
Car Oxygen sensor Diagram
Step 1 - Locate the hood release activation lever and operate it. This will "pop" the hood open and allow you access to the engine.
Step 2 - Once the hood is open and secure locate the failed sensor. Most sensors are located in the head pipe or downpipe and behind thecatalytic converter.
Step 3 - Spray a anti-rust lubricate over the sensor near the mounting threads and seat of the oxygen sensor and allow to penetrate.
Step 4 - Locate and release the electrical connector. (Note: Some sensor wire leads can be quite long so you may need to follow the wiring harness to locate the connector)
Step 5 - Now that the electrical connector is disconnected use a wrench to loosen the sensor by turning the sensor counter clockwise. Continue to loosen the sensor until free.
Step 6 - Use a wire brush to help clean the threaded port to ensure a proper seal of the new sensor.
Step 7 - Match the old sensor to the new sensor to make sure you have the correct part. (Note: some replacement sensors have a universal electrical connector that will need to be configured to the wiring of the old sensor).
Step 8 - Install the new sensor and firmly tighten the sensor's sealing ring against the threaded port in the exhaust system.
Step 9 - Re-connect the electrical connector and secure the wiring harness into the plastic holders. (If any)
Step 10 - If the car has diagnostic trouble codes, they will need to be cleared in all cars built after 1996. If the codes are not cleared the check engine light will remain illuminated until the system cycles the code out and clears itself.
Car Oxygen sensor removal socket tool
- Buy a specially designed socket can be used to aid in the removal of hard to access sensors