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Home >> Toyota >> 2010 >> Matrix Base, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control (SFI) System (2ZR-FE) (Diagnostic Codes (P0441-P2A00) & Symptom Tests) >> SFI System >> DTC P050A: Cold Start Idle Air Control System Performance >> Procedure
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DTC P050A: Cold Start Idle Air Control System Performance: Procedure

  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050A) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
    5. Read the DTCs.

      Result

      Result Proceed to
      DTC P050A is output A
      DTC P050A and other DTCs are output B

      HINT: 

      If any DTCs other than P050A are output, troubleshoot those DTCs first.

    B → See step   16 

    A: Go to next step 

  2. READ VALUE USING TECHSTREAM (FUEL TRIM) 

    HINT: 

    Calculate the total fuel trim values to check the characteristic deviation of the mass air flow meter.

    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Data List / Short FT #1 and Long FT #1.
    5. Read the values displayed on the Techstream.
    6. Add together the Short FT #1 and Long FT #1 values to obtain the total Fuel Trim.

      OK

      Total of Short FT #1 and Long FT #1 values is between -20% and 20%.

    NG → See step   5 

    OK: Go to next step 

  3. INSPECT THROTTLE BODY ASSEMBLY 
    1. Check that there are no deposits around the throttle valve.

      OK

      No deposits around the throttle valve.

    NG → See step   10 

    OK: Go to next step 

  4. REPLACE ECM 
    1. Replace ECM. Refer to REMOVAL .

    NEXT → See step   15 

  5. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE CAMSHAFT TIMING OIL CONTROL VALVE ASSEMBLY) 
    1. Check the camshaft timing oil control valve assembly for intake camshaft.
      1. Connect the Techstream to the DLC3.
      2. Start the engine.
      3. Turn the Techstream on.
      4. Turn the A/C switch to ON.
      5. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 1).
      6. Check the engine speed while operating the camshaft timing oil control valve assembly (for intake camshaft) using the Techstream.

        Result

        Techstream Operation Specified Condition
        OFF Normal engine speed
        ON Engine idles roughly or stalls
        (soon after camshaft timing oil control valve assembly switched from OFF to ON)

        HINT: 

        If the result is not acceptable, cool the engine and perform the Active Test again.

      7. Start the engine when the engine coolant temperature is 30°C (86°F) or less.
      8. Turn the Techstream on.
      9. Turn the A/C switch to ON.
      10. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 1).
      11. Check the engine speed while operating the camshaft timing oil control valve assembly using the Techstream with the engine coolant temperature is 50°C (122°F) or less.

        Result

        Techstream Operation Specified Condition
        Camshaft timing oil control valve assembly OFF Normal engine speed
        Camshaft timing oil control valve assembly ON Engine idles roughly or stalls
        (soon after camshaft timing oil control valve assembly switched from OFF to ON)

    NG → See step   11 

    OK: Go to next step 

  6. CHECK PCV SYSTEM 
    1. Start the engine.
    2. Pinch the positive crankcase ventilation (PCV) hose.
    3. Check the engine rpm.

      OK

      The engine rpm rises when the PCV hose is pinched.

    NG → See step   12 

    OK: Go to next step 

  7. CHECK AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY 
    1. Visually check that the air cleaner filter element is not excessively contaminated with dirt or oil.

      OK

      The air cleaner filter element is not excessively contaminated with dirt or oil.

    NG → See step   13 

    OK: Go to next step 

  8. CHECK INTAKE SYSTEM 
    1. Check the intake system for vacuum leaks. Refer to ON-VEHICLE INSPECTION .

      OK

      No leaks from the intake system.

    NG → See step   14 

    OK: Go to next step 

  9. REPLACE MASS AIR FLOW METER 
    1. Replace the mass air flow meter. Refer to REMOVAL .

    NEXT → See step   15 

  10. REPLACE THROTTLE BODY ASSEMBLY 
    1. Repair or replace the throttle body assembly. Refer to REMOVAL .

    NEXT → See step   15 

  11. CHECK AND REPAIR VVT SYSTEM 

    HINT: 

    Check the VVT system for intake camshaft. Refer to INSPECTION PROCEDURE .

    NEXT → See step   15 

  12. REPAIR OR REPLACE PCV SYSTEM 

    NEXT → See step   15 

  13. REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY 

    NEXT → See step   15 

  14. REPAIR OR REPLACE INTAKE SYSTEM 

    NEXT: Go to next step 

  15. CHECK WHETHER DTC OUTPUT RECURS (DTC P050A) 
    NOTE:

    For this operation, the engine must be cold (the same level as the engine coolant temperature recorded in the freeze frame data).

    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Clear DTCs. Refer to DTC CHECK / CLEAR .
    5. Start the engine and idle it for one minute.

      OK

      Stable fast idle

    6. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.
    7. Check for pending DTCs.

      OK

      No pending DTC is output.

    NEXT → END 

  16. GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART 
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