Manifold Pressure/Vacuum Sensor: Testing and Inspection

1. Inspect MAP sensor vacuum hose connections at throttle body and sensor. Repair as necessary.
2. With ignition switch On and engine Off, check output voltage at sensor connector terminal B(marked on sensor body). Voltage should be 4-5 volts.
3. Test ECU connector terminal 33 for voltage. Voltage should be the same as outlined in step 2. If not, repair wire harness as necessary.
4. With ignition switch On, check supply voltage at sensor connector terminal C. Voltage should be 4.5-5.5 volts.
5. Test ECU connector 16 for voltage. Voltage should be the same as outlined in step 4. If not, repair wire harness as necessary.
6. Test MAP sensor ground circuit at sensor connector terminal A and ECU connector terminal 17. Repair wire harness as necessary.
7. Test MAP sensor ground circuit again at ECU connector terminals 17 and 2 with a suitable ohmmeter. If an open circuit is indicated, check for a defective ground connection on the flywheel/drive plate housing near the starter motor and repair as necessary. If ground connection is satisfactory, replace ECU. If ECU connector terminal 17 indicates 12 volts, repair circuit before replacing ECU.