In many models, lamda sensors are used to control the mixture. If the lambda sensor is removed (e.g. by installing a different exhaust system) warning lights, etc. might be activated. You may also experience jerking at cruising speed and lean running. The O2 sensor eliminator replaces the lambda sensor in the original plug, reporting the expected optimum values to the injection system. No more jerking and no more warnings. Note! In some vehicles two lambda sensors are used, so two O2 sensor eliminators are also required!