What does MAP mean on a car?

[DelEverly]

In automobiles, MAP stands for Manifold Absolute Pressure sensor, which measures changes in absolute pressure (vacuum) within the intake manifold and converts them into voltage signals. These signals are then transmitted to the Engine Control Unit (ECU). Based on this data, the ECU determines the engine load and, in combination with the engine speed signal, calculates the appropriate fuel injection quantity. Below is an introduction to the intake manifold: 1. Composition: The intake manifold absolute pressure sensing element consists of a silicon chip. A pressure diaphragm is etched onto the silicon chip, with a piezoresistive strain gauge forming a Wheatstone bridge. In addition to the pressure diaphragm, signal processing circuits are integrated onto the silicon chip. 2. Silicon Chip: The silicon chip is only a few micrometers thick, so changes in intake manifold pressure cause the silicon chip to deform. The piezoresistive strain gauge also deforms, altering its resistance. After processing by the signal processing circuits on the silicon chip, a voltage signal that is linearly related to the pressure is generated.