Manifold Pressure/Vacuum Sensor: Testing and Inspection

Manifold Absolute Pressure (MAP) Sensor:

To perform a complete test of MAP sensor and its circuitry, refer to DRB scan tool and appropriate Powertrain Diagnostics Procedures. To test the MAP sensor only, refer to the following:

Rubber L-shaped Fitting - MAP Sensor-to-Throttle Body:

1. Inspect the rubber L-shaped fitting from the MAP sensor to the throttle body. Repair as necessary.

CAUTION: When testing the MAP sensor, be sure that the harness wires are not damaged by the test meter probes.

MAP Sensor Connector Terminals:

2. Test the MAP sensor output voltage at the MAP sensor connector between terminals A and B. With the ignition switch ON and the engine OFF; output voltage should be 4-to-5 volts. The voltage should drop to 1-to-2.1 volts with a hot, neutral idle speed condition. Voltage at higher elevations may be slightly lower 1-to-2.1 volts.
3. Test powertrain control module (PCM) cavity A-27 for the same voltage described above to verify the wire harness condition. Repair as necessary.
4. Test MAP sensor supply voltage at sensor connector between terminals A and C with the ignition ON. The voltage should be approximately 5 volts (±0.5V). Five volts (±0.5V) should also be at cavity A-17 of the PCM wire harness connector. Repair or replace the wire harness as necessary.
5. Test the MAP sensor ground circuit at sensor connector terminal-A and PCM connector A-4. Repair the wire harness if necessary.