Walker Products 250-24701 4-Wire Oxygen Sensor

The oxygen sensor is a device which determines the oxygen content of the exhaust gas. Located in the exhaust system, the oxygen sensor produces a voltage proportional to the amount of oxygen in the exhaust versus the air (750 mV rich). This data is used to control the air-fuel mixture through PORT or TFI injectors and carburetors. Sensors are monitored or checked anywhere from 4 to 100 times per second. The air-fuel mixture is thus always moving from rich to lean averaging very close to stoichiometric (ideal) ratios. The ceramic sensor body is contained in a housing which protects it against mechanical effects and facilitates mounting. The ceramic body is made of stabilized zirconium dioxide (zirconia). Its surfaces are coated with electrodes made of a gas-permeable platinum layer. In addition, a porous ceramic coating has been applied to the side exposed to the exhaust gas. This coating prevents contamination and erosion of the electrode surfaces by combustion residue and particulates in the exhaust gases.

Walker Products began supplying the fuel system needs of the automotive industry in 1946. Today Walker is one of the largest, privately owned manufacturers of fuel system components and engine sensors, and has served the needs of the worldwide automotive aftermarket. We are committed to supplying products manufactured to meet or exceed OEM standards and specifications. This effort is backed by our own manufacturing, product management and engineering staff to ensure it is maintained and accurate in the production of quality parts, vehicle applications, instruction sheets and technical support. Our products include Carburetor and Fuel Injection Repair Kits, Oxygen Sensors and other Engine Management products such as Throttle Position Sensors, Cam and Crankshaft Sensors, Fuel Injectors, Spark Plug Wires and Gaskets. As an ISO 9001:2008/TS16949 certified company, we are committed to supplying the highest quality products.