Working Principal

Working Principal

Although they have many types and different appearances, oxygen sensors have certain working principals: Titania,Air-fuel ratio,Wide-band and Extreme.

Air-fuel ratio working principal:

Once there is an oxygen concentration difference, the oxygen ions would flow from the higher concentration side to the lower one which would cause an electromotive force. The ideal air-fuel ratio is a divide line which would create a great electromotive force by the differences of two sides' ions.

Wide-band Working Principal:

Base material is also zirconia, while wide-band's working principal is totally different from the air-fuel ratio type. Their main difference is wide-band tells the exact figure of the oxygen content in the exhaust gas while air-fuel ratio sensor can only show the rich or lean status. Also the wide-band normally has 5 wires with 5 or 6 pins.

Obviously, once oxygen content in the exhaust gas can be continously measured, ECU would have a more precise fuel injection control. Therefore engine would have a more effective fuel consumption and power performance, meanwhile emissions gets better.

Extreme current:

Extreme current shares the same characteristics with wide-band. They can continuously get the exact figure of the oxygen content in the exhaust gas. But their range is different. Wide-band is used for the whole process monitoring of rich and lean mixture while Extreme Current is more suitable for lean mixture. Therefore, Extreme Current is usually applied to the engines with tech of Lean mixture burning.

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