Oxygen Sensor O2
Oxygen Sensor (02) The oxygen sensor or Lambda sensor (AKA O2 Sensor) in your vehicle is one of the key components in the fuel injection system. Its job is to measure the amount of oxygen required to burn any fuel remaining in the exhaust stream and relay that information back to the computer PCM (Powertrain Control Module) where it is compared with other live information so that adjustments can be made to maximize fuel efficiency and power via proper air-fuel mixture and ignition timing in the engine. Oxygen sensors do this through a chemical reaction inside the sensor itself; in this article we will explain the evolution and application of this very important piece of the fuel injection puzzle Early oxygen sensors were simple one or two wire sensors that gave feedback to the computer through a chemical reaction within the sensor that creates voltage. These early sensors had to warm up before they became active, which means they didn’t work until they had reached the operating temperature in the exhaust system required for the chemical reaction to work properly as well as the engine reaching a close-to-operating coolant temperature. While extremely simple, they worked fine with the basic fuel injection systems of the time, which had extremely slow BAUD rates (rate at which information is processed in the computer). As technology improved, the sensors had to be improved upon as well. Oxygen sensors work through a chemical reaction. The core or element of the sensor is Zirconia ceramic with a thin layer of platinum. Since these materials are reactive and are applied as layers they will eventually wear out reducing their efficiency, you should follow your vehicle manufacturers recommendations as far as replacement. A common misconception is that the sensors measure the actual amount of oxygen in the exhaust, when in reality they measure the amount of oxygen required to burn any fuel that is remaining in the exhaust stream. For instance a rich condition (too much fuel) will cause a higher voltage reading since it is creating a demand for oxygen within the sensor to burn the fuel, whereas a lean condition will do the exact opposite. The voltage created by the sensor is then relayed to the computer where it will compare it with other live information to make the necessary mixture and timing adjustments.
Oxygen Sensor Cut Away The oxygen sensor is in continuous communication with the engine control unit giving it the information necessary to adjust fuel delivery for optimum combustion. When the engine is cold the oxygen sensor reads slowly, a heating element has been installed to correct this problem and help the sensor operate correctly until the engine has reached operating temperature. When the throttle is wide open and under max load the oxygen sensor will go to full voltage output until normal driving conditions return. Typically changing an oxygen sensor when necessary is a simple process. Most solutions to oxygen sensor problems result in changing the oxygen sensor, but always be sure there are no vacuum leaks present in the intake system, this can give a false oxygen sensor trouble code. Due to the severe usage environment the sensor endures, it is common for most sensors to last approximately 75,000 miles, however it is not uncommon for an oxygen sensor to last only 40,000 miles depending on your driving habits and vehicle operating conditions. Over the life of the oxygen sensor soot build up can occur on the sensing probe which can result in inaccurate readings. This can cause your engine to run rough and consume excessive fuel. If further technical assistance is needed, ask our team of certified car repair technicians. Related Car Repair Information
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