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Throttle Body: Inspection

  1. THROTTLE SENSOR (METHOD WITH CIRCUIT TESTER) 
    NOTE: Individual difference of the accelerator pedal may not be corrected sufficiently on the ECM side after DTCs were cleared or the battery was removed and installed on the vehicle. Therefore, when the reference voltage is not reached after following the procedure, repeat the ignition switch ON (engine OFF) and ignition switch OFF operations 40 times at intervals of three seconds or more, and then measure the voltage again.
    1. Remove the glove box lower cover. REMOVAL .
    2. Remove the lower inner trim of passenger's side. REMOVAL
    3. Turn over the floor mat of passenger's seat.
    4. Remove the protect cover.
      Fig 1: Locating Protecting Cover Mounting Screws
      G08538832Courtesy of SUBARU OF AMERICA, INC.
    5. Remove the nuts and bolts which hold the ECM to the bracket.
      Fig 2: Locating ECM Mounting Nuts
      G08538833Courtesy of SUBARU OF AMERICA, INC.
    6. Turn the ignition switch to ON. (engine OFF)
    7. Measure the voltage between ECM connector terminals
      Fig 3: Measuring Voltage Between ECM Connector Terminals
      G07662677Courtesy of SUBARU OF AMERICA, INC.
      Throttle Sensor Accelerator Pedal Terminal No. Standard
      Main Not depressed (Full closed) 18 (+) and 29 (-) Approx. 0.6 V
      Depressed (Full opened) Approx. 3.96 V
      Sub Not depressed (Full closed) 28 (+) and 29 (-) Approx. 1.48 V
      Depressed (Full opened) Approx. 4.17 V
    8. After inspection, install the related parts in the reverse order of removal.
  2. THROTTLE SENSOR (METHOD WITH SUBARU SELECT MONITOR) 
    NOTE: Individual difference of the accelerator pedal may not be corrected sufficiently on the ECM side after DTCs were cleared or the battery was removed and installed on the vehicle. Therefore, using the Subaru Select Monitor, check that the accelerator opening angle signal indicates 100%, when the accelerator pedal is fully depressed, and then perform the inspection.
    1. Turn the ignition swtich to ON. (engine OFF)
    2. While reading the accelerator opening angle signal and throttle sensor voltage using Subaru Select Montior, depress the accelerator pedal to full open and full closed. OPERATION .
      Throttle Sensor Acceleration opening angle signal Standard
      Main 0.0 % Approx. 0.6 V
      100.0 % Approx. 3.96 V
      Sub 0.0 % Approx. 1.48 V
      100.0 % Approx. 4.17 V
  3. OTHER INSPECTIONS 
    1. Check that the throttle body has no deformation, cracks or other damages.
    2. Check that the engine coolant hose has no cracks, damage or loose part.