There is a Chevrolet oxygen sensor on your car that provides vital information to the computer so the engine will perform smoothly and efficiently. All newer models of Chevrolet have one that is located on the exhaust pipe or exhaust manifold. Like all oxygen sensors, and could wear out or fail to function correctly over time and will require replacement. If the oxygen sensor on your Chevrolet fails, the check engine light will appear on your dash. This is a signal from the onboard computer that there is a problem. Each sensor failure, including the oxygen sensor, on your engine has a specific code that the computer will register and display. All Chevrolet models have their own set of codes which can be found in the service manual at your local auto parts store. The manual will also show you how to retrieve and identify the codes. The responsibility of the oxygen sensor is to compare the level of oxygen in the atmosphere to what is in the exhaust gases after the fuel is burnt. This information is sent to the onboard computer which allows for the correct air to fuel ratio to be dispersed into the engine's combustion chambers. Because the oxygen levels across the nation are slightly different due to pressure and altitude, a properly operating oxygen sensor is required so the engine will be able to perform at its optimum level of efficiency. Replacement of the Chevrolet oxygen sensor is simple. Once located, the wire has to be detached and a wrench used to remove the old sensor and the new one put in its place. Make sure the engine is cool before undertaking this procedure. With the wire reattached, this vital sensor can now supply the required information to your onboard computer it needs.