Thimble Oxygen Sensor
Conical ceramic sensing element
Thimble oxygen sensor also known as the "Conical Lambda Sensor", is a switch-type lambda sensor that detects oxygen contents within the exhaust gas. The ceramic sensing element is pressed formed to conical design, hence "Thimble". It is a traditional and earliest type of oxygen (O2) sensor.
The thimble oxygen sensors function as rich and lean indicators generally come in 1 to 4 wires. With 1 and 2 wires, known as an unheated oxygen sensor, usually located close to the engine room and relies on the surrounding heat to reach operational temperature. With 3 and 4 wires O2 sensor, it integrated heating element, known as a heated oxygen sensor, allowing the sensor to be located downstream after the catalytic converter.
Ceradex's patented single-cell thimble technology enables our sensors to be more resistant to the harsh environment of the engine room and exhaust system. With added specialized protective coating on the ceramic cell surface, resulting in a longer sensing lifespan.