GM Genuine Parts Manifold Absolute Pressure (MAP) Sensors are designed, engineered, and tested to rigorous standards, and are backed by General Motors. The MAP sensor is a part of the fuel and engine management system. Its signal is used by the engine control module along with the throttle position sensor to calculate the amount of air entering the engine so that the correct amount of fuel is injected for optimum combustion. GM Genuine Parts are the true OE parts installed during the production of or validated by General Motors for GM vehicles. Some GM Genuine Parts may have formerly appeared as ACDelco GM Original Equipment (OE).