Experiment 3, Manifold Absolute Pressure (MAP)

Q. Does the map sensor match the manufactures specifications, why or why not?

A. No, the values are not matching with the specifications. It may be because of the leakage in measuring gauge or in manifold

Q. Does a map sensor read vacuum or pressure?

A. Vacuum

Q. Explain the internal operation of this sensor and why the output voltage changes?

A. There is a silicon chip inside the reference chamber. On one side of the chip is a reference pressure. This reference pressure is either a perfect vacuum or a calibrated pressure, depending upon application. On other side is pressure to be measured. Silicon chip changes it resistance with changes in pressure. When chip flexes with the change in pressure, the electric resistance of the chip changes. This changes in resistance alters the voltage signal. (Lesson 2, Sensors: Theory class notes)