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Home >> Pontiac >> 2003 >> Aztek AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Self-Diagnostics >> Diagnostic Tests >> DTC P0101: MAF Sensor Performance >> Diagnostic Procedures
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Diagnostic Procedures

  1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM.
  2. Attempt to start engine. Does the engine start? If yes, go to next step. If no, go to step  6.
  3. Monitor the Diagnostic Trouble Code (DTC) Information with the scan tool. Does the scan tool display any other DTCs set? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, go to next step.
  4. Observe the Freeze Frame/Failure Records data for this DTC. Turn ignition off for 30 seconds. Start engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see DIAGNOSTIC AIDS .
    5. NOTE: The Altitude vs. Barometric Pressure table indicates a pressure range for a given altitude under normal weather conditions. Weather conditions consisting of very low or very high pressure and/or temperature may cause a reading to be slightly out of range.
  5. Turn ignition on, with engine off. Observe the MAP sensor kPa parameter with a scan tool. The MAP sensor pressure should be within the specified range for your altitude. Refer to SENSOR OPERATING RANGE CHARTS - TRUCKS article. Is MAP sensor pressure within the specified range as indicated on the Altitude vs Barometric Pressure table? If yes, go to next step. If no, diagnose MAP sensor. See DTC P0107: MAP SENSOR CIRCUIT - LOW VOLTAGE or DTC P0108: MAP SENSOR CIRCUIT - HIGH VOLTAGE 
  6. Allow the engine to reach operating temperature. Observe the MAP sensor voltage with a scan tool. Is the MAP sensor voltage 0.8-4.0 V? If yes, go to next step. If no, diagnose MAP sensor. See DTC P0107: MAP SENSOR CIRCUIT - LOW VOLTAGE or DTC P0108: MAP SENSOR CIRCUIT - HIGH VOLTAGE  .
  7. Idle engine. Observe the MAP sensor kPa with a scan tool. Increase the engine speed slowly to 3000 RPM and then back to idle. Does the MAP sensor kPa change smoothly and gradually through the specified range of the test? If yes, go to next step. If no, diagnose MAP sensor. See DTC P0107: MAP SENSOR CIRCUIT - LOW VOLTAGE or DTC P0108: MAP SENSOR CIRCUIT - HIGH VOLTAGE  .
  8. Turn ignition off. Turn ignition on, with engine off. Observe the TP sensor angle from closed throttle to wide-open throttle. Depress completely and then release the accelerator pedal. Does the scan tool indicate that the TP sensor angle changed smoothly and completely through 0-100%? If yes, go to next step. If no, see DTC P0121: TP SENSOR PERFORMANCE .
  9. Inspect for the following conditions:
    • A restricted or collapsed air intake duct.
    • A dirty or deteriorating air filter element.
    • Any objects blocking the air inlet screen of the MAF sensor.
    • Any debris on the sensing elements of the MAF sensor.
    • Any vacuum leak downstream of the MAF sensor.
    • A poor vacuum connection at the MAP sensor.
    • A skewed or stuck ECT sensor.
    • High resistance in the ground circuit of the ECT sensor.
    • A restricted exhaust system.

    Did you find and correct the condition? If yes, go to step  14. If no, go to next step.

  10. Disconnect the MAF sensor harness connector. Turn ignition on, with engine off. Connect a test light between the ignition 1 voltage circuit of the MAF sensor and a good ground. Connect a DVOM to the probe of the test light and a good ground. Is voltage less than battery voltage? If yes, go to step  13. If no, go to next step.
  11. Test for an intermittent and for a poor connection at the MAF sensor. Did you find and correct the condition? If yes, go to step  14. If no, go to next step.
  12. Repair the high resistance in the ignition 1 voltage circuit of the MAF sensor. After repairs, go to step  14.
  13. Replace MAF sensor. See REMOVAL & INSTALLATION - AZTEC & RENDEZVOUS article. After repairs, go to next step.
  14. Clear the DTCs with a scan tool. Turn ignition off for 30 seconds. Start engine. Operate the vehicle within the Conditions for Running DTC. See CONDITIONS FOR RUNNING DTC . Does the DTC run and pass? If yes, go to next step. If no, go to step  2.
  15. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.
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