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Manifold Absolute Pressure Sensor Switching Control Inspection

1. Warm up the engine to normal operating temperature and let it idle.




2. Disconnect the vacuum hose from the MAP sensor solenoid valve side of the MAP sensor.
3. Put a finger on the port of the MAP sensor solenoid valve and verify that no vacuum is felt.




4. Open the throttle valve. Increase the engine speed to 4,000 rpm and hold it.
5. Put a finger on the port of the MAP sensor solenoid valve and verify that vacuum is felt.
- If not as specified, inspect the following.
- MAP sensor solenoid valve
- Vacuum hose for damage or looseness
- PCM terminal voltages
3E (MAF sensor)
4P (MAP sensor solenoid valve)
4AH, 4AL (CKP sensor)
3X (CTP switch)