MAP (Manifold Absolute Pressure) Sensor

Visit our Auto Parts comparison shopping area to buy a MAP Sensor now!

The Manifold Absolute Pressure MAP sensor is a sensor that is attached to the intake manifold on a car's engine. The MAP sensor responds to changes in the intake manifold pressure (vacuum) and provides a reading of "engine load".

How it works is 5 volts DC is supplied to the sensor from the PCM (powertrain control module). Inside the MAP sensor there is a resistor that moves in relation to intake manifold pressure. The resistor varies the voltage between about 1V to 4.5V (depending on engine load) and that voltage signal is returned to the PCM to indicate manifold pressure (vacuum). This signal is essential for the PCM to determine fuel delivery and is also used some times to determine if the EGR Valve is operating properly.

See the photo (above) of a MAP sensor, yours may or may not look like this. For further reading, here are some trouble codes that may come up related to MAP sensors - P0101 - P0106 - P0107

Also, check out the MAP Sensor page at Wikipedia for more detailed information. Below is a video we found at YouTube that shows you clearly how to diagnose your MAP sensor.