Manifold Pressure/Vacuum Sensor: Testing and Inspection

MANIFOLD ABSOLUTE PRESSURE SENSOR

Component Function Check


1. CHECK MANIFOLD ABSOLUTE PRESSURE SENSOR FUNCTION

WITH CONSULT
1.Start engine.
2.Check "MAP SENSOR" in "DATA MONITOR" mode with CONSULT.





WITHOUT CONSULT
1.Start engine.
2.Check the voltage between ECM harness connector and ground.





Is the inspection result normal?
YES- INSPECTION END
NO- Proceed to "Diagnosis Procedure" .


Diagnosis Procedure


1. CHECK INTAKE SYSTEM

Check the following for connection.
- Air duct
- Vacuum hoses
- Intake air passage between air duct and intake manifold.
Is the inspection result normal?
YES- GO TO 2.
NO- Repair or replace ground connection.

2. CHECK GROUND CONNECTION

1.Turn ignition switch OFF.
2.Check ground connection E21 and E38. Refer to Ground Inspection in "Circuit Inspection" Circuit Inspection.
Is the inspection result normal?
YES- GO TO 3.
NO- Repair or replace ground connection.

3. CHECK MAP SENSOR POWER SUPPLY CIRCUIT

1.Disconnect manifold absolute pressure (MAP) sensor harness connector.
2.Turn ignition switch ON.
3.Check the voltage between MAP sensor harness connector and ground.





Is the inspection result normal?
YES- GO TO 4.
NO- Repair open circuit, short to ground or short to power in harness or connectors.

4. CHECK MAP SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.Turn ignition switch OFF.
2.Disconnect ECM harness connector.
3.Check the continuity between MAP sensor harness connector and ECM harness connector.





4.Also check harness for short to ground and power.
Is the inspection result normal?
YES- GO TO 5.
NO- Repair open circuit, short to ground or short to power in harness or connectors.

5. CHECK MAP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.Check the continuity between MAP sensor harness connector and ECM harness connector.





2.Also check harness for short to ground and power.
Is the inspection result normal?
YES- GO TO 6.
NO- Repair open circuit, short to ground or short to power in harness or connectors.

6. CHECK MAP SENSOR

Refer to "Component Inspection (MAP sensor)" .
Is the inspection result normal?
YES- GO TO 7.
NO- Replace MAP sensor.

7. CHECK INTERMITTENT INCIDENT

Refer to "Intermittent Incident" Intermittent Incident.
- INSPECTION END


Component Inspection (MAP sensor)


1. CHECK MAP SENSOR-I

1.Turn ignition switch OFF.
2.Start engine and warm it up to normal operating temperature.
3.Turn ignition switch OFF, wait at least 5 seconds and then turn ON.
4.Check the voltage between ECM harness connector terminals as follows.





NOTE:
- To avoid the influence of intake manifold vacuum, check the voltage 1 or more minutes past after engine is stopped.
- Because the sensor is absolute pressure sensor, output value may differ depending on atmospheric pressure and altitude.
5.Measure the atmospheric pressure.
NOTE:
As the atmospheric pressure described on the synoptic chart is the value at sea level, compensate the pressure with the following chart.





6.Check the manifold absolute pressure sensor value corresponding to the atmospheric pressure.










Is the inspection result normal?
YES- GO TO 2.
NO- Replace MAP sensor.

2. CHECK MAP SENSOR-II

1.Start engine and let it idle.
2.Check intake manifold vacuum.
3.Check the voltage between ECM harness connector terminals as per the following.





4.Confirm the difference of the voltage when engine is stopped and at idling is within the values shown in the following chart.





Is the inspection result normal?
YES- INSPECTION END
NO- Replace MAP sensor.