Manifold Absolute Pressure (MAP) Sensor (Except 3.3L & 3.8L)

The MAP sensor measures changes in manifold pressure. Changes in manifold pressure result from engine load and speed changes. The MAP sensor converts these changes in manifold pressure into a voltage output signal to ECM (about 1.5 volts at idle to about 4.5 volts at WOT). The ECM can monitor these signals and adjust air/fuel ratio and ignition timing under various operating conditions.

If MAP sensor fails, the ECM will substitute a fixed MAP value and will use the TPS to control fuel delivery. A fault in the MAP circuit should set a related trouble code. If a related trouble code is not present and MAP sensor is suspected of causing a driveability problem, perform functional check of MAP sensor. see ENGINE SENSORS & SWITCHES in appropriate I - SYS/COMP TESTS article in this section.