Auto Repair Parts
Oxygen Sensors - Why does my car have four, and can I replace one myself?
An oxygen sensor (also known as an O2 sensor or Lambda sensor) is a sensor designed to generate a reading based on the content of oxygen in an automotive exhaust system. The sensor itself is made of a ceramic compound with porous-shaped electrodes coated in platinum, surrounded by a protective metal shell casing. O2 sensor casings are threaded, and the entire unit is designed to screw in until it reaches a half-in, half-out position on the exhaust pipe. Modern oxygen sensors are heated to ensure they reach operating temperature quickly.