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Home >> Toyota >> 2008 >> Prius Base >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> SFI System >> DTC P0101 Mass Air Flow Circuit Range / Performance Problem >> Inspection Procedure
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Inspection Procedure

HINT:

Read freeze frame data using Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0101) 
    1. Connect Techstream to the DLC3.
    2. Turn the power switch ON (IG).
    3. Turn the tester on.
    4. Select the following menu items: Powertrain / Engine and ECT / Trouble Code.
    5. Read the DTCs.

      Result 

      RESULT CHART

      Display (DTC Output) Proceed to
      P0101 A
      P0101 and other DTCs B

      HINT:

      If any DTCs other than P0101 are output, troubleshoot those DTCs first.

    B:  GO TO DTC CHART 

    A: Go To Next Step 

  2. CHECK AIR INDUCTION SYSTEM 
    1. Check the air induction system for vacuum leaks.

      OK: 

      No leaks in air induction system. 

    NG: REPAIR OR REPLACE AIR INDUCTION SYSTEM 

    OK: Go To Next Step 

  3. CHECK PCV HOSE (HOSE CONNECTION) 

    OK: 

    PCV hose is connected correctly and is not damaged. 

    NG: REPAIR OR REPLACE PCV HOSE 

    OK: REPLACE MASS AIR FLOW METER