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 mV ~ 1,500 mV at idle (no load)
3. Approx. 1,700 mV ~ 1,900 mV at 2000 RPM (no load)
  
  Fig 1: Scantool Display - Sensor Data At Idle
  
  Fig 2: Scantool Display - Sensor Data At 2000 RPM
  
  Fig 3: Scantool Display - Sensor Data At 3000 RPM
  
  Fig 4: Scantool Display - Sensor Data At Open In Signal Circuit
Is the sensor's signal within specifications?
YES
1. Substitute with a known-good PCM and check for proper operation. If the problem is corrected, replace PCM and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO
1. Check MAF sensor for contamination, deterioration, or damage. Substitute with a known-good MAF sensor and check for proper operation. If the problem is corrected, replace MAF sensor and go to "VERIFICATION OF VEHICLE REPAIR " procedure.