Ranger 2WD V6-177 2.9L (1989)
Manifold Pressure/Vacuum Sensor: Description and Operation
The MAP sensor measures manifold vacuum using a frequency. This gives the ECA information on engine load. The ECA used the MAP sensor as a
barometric sensor for altitude compensation, updating the ECA during "Key On/Engine Off" and every wide-open throttle. It also supplies information
for spark advance, EGR flow and air/fuel ratio.
