Component Inspection

Connect scantool to Data Link Connector (DLC).
Warm up the engine to normal operating temperature.
Monitor the "MASS AIR FLOW" parameter on scantool.
1. Specification
  1. Approx. 900 mV at IG KEY: ON & Engine: OFF
  2. Approx. 1,300~1,500 mV at idle (no load)
  3. Approx. 1,700~1,800 mV at 2000 RPM (no load)
    
    Fig 1: Scantool Screen Display - Mass Air Flow Parameter
Is the sensor's signal near the specified value?
YES
1. MAF sensor is OK.
2. Possibility of ECM fail.
3. Test with a new ECM and check for proper operation. If problem is corrected replace ECM and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO
1. Test with a new MAF sensor and check for proper operation. If problem is corrected, replace MAF sensor.