What Does A Map Sensor Do On A Diesel Engine. In fuel injected automotive engines a manifold absolute pressure map sensor is used to continuously monitor the amount of air flowing into the engine so the computer can calculate air density adjust the amount of fuel to spray into the combustion chamber and adjust the ignition timing. Map sensors are set to zero from the factory.

Map sensors respond to the air pressure within the intake manifold and allow the engine control module ecm to estimate two important parameters. Engines that use a map sensor are typically fuel injected the manifold absolute pressure sensor provides instantaneous manifold pressure information to the engine s electronic control unit ecu. The data is used to calculate air density and determine the engine s air mass flow rate which in turn determines the required fuel metering for optimum.

The manifold absolute pressure map sensor is used by the powertrain control module pcm for engine load input.

By using an air mass sensor mass air flow or maf or an intake air pressure sensor manifold absolute pressure or map combined with an inlet air temperature sensor. By using an air mass sensor mass air flow or maf or an intake air pressure sensor manifold absolute pressure or map combined with an inlet air temperature sensor. The ecm uses map sensor data to run crucial calculations such as engine load fuel injector pulse and spark advance. Map sensors are set to zero from the factory.