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Home >> Subaru >> 2022 >> WRX Base, Automatic CVT Trans >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Fuel Injection System >> Fuel Injector >> Replacement
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Fuel Injector: Replacement

  1. Remove the O-ring (A) and support disc (B).
    G13198235Courtesy of SUBARU OF AMERICA, INC.
  2. Gradually expand the fuel injector seal and remove the fuel injector seal.
    CAUTION:
    • Be careful not to apply too much force when pinching the fuel injector seal, or the fuel injector groove may be damaged. 
    • If the tip of the fuel injector assembly is hit or the assembly is dropped, replace the fuel injector assembly with a new one. 
    G13198236Courtesy of SUBARU OF AMERICA, INC.
  3. Remove the decoupling.
    NOTE:

    Perform this procedure only when required. 

    G13198237Courtesy of SUBARU OF AMERICA, INC.
  4. Install the fuel injector seal.
    1. Remove carbon from area (A) shown in the figure (fuel injector seal groove).
      CAUTION:
      • Do not attempt to clean the tip. 
      • Do not use a wire-brush. 
      • If the tip of the fuel injector assembly is hit or the assembly is dropped, replace the fuel injector assembly with a new one. 
      G13198238Courtesy of SUBARU OF AMERICA, INC.
    2. Set the ST1 on the end of fuel injector, and install new fuel injector seal (A) on the ST1.
      CAUTION:

      When setting the fuel injector seal on the ST1, be careful not to set it obliquely, or the seal is stretched and become hard to be fixed. 

      NOTE:
      • Apply liquid paraffin to the fuel injector seal and fuel injector groove. 
      • Do not let liquid paraffin contact inside the fuel injector and the port located at the tip end of the fuel injector. 

      Preparation tool: 

      ST1: GUIDE (18271AA030)

      G13198239Courtesy of SUBARU OF AMERICA, INC.
    3. Use fingers to push down on the fuel injector seal installed to the ST1, and install it to the fuel injector groove as shown in the figure.
      CAUTION:

      Make sure that the entire perimeter of the fuel injector seal fit in the groove. 

      Preparation tool: 

      ST1: GUIDE (18271AA030)

      G13198240Courtesy of SUBARU OF AMERICA, INC.
    4. Set the ST2 on the fuel injector as shown in the figure.

      Preparation tool: 

      ST2: ADJUSTER (18271AA040)

      G13198241Courtesy of SUBARU OF AMERICA, INC.
    5. Slowly press the ST2 downward in the direction of arrow and seat the fuel injector seal into the fuel injector groove.
      CAUTION:

      Be careful not to let the fuel injector seal get caught in the ST2 and the fuel injector groove. If it gets caught, repeat the procedure from the step   2 . 

      Preparation tool: 

      ST2: ADJUSTER (18271AA040)

      G13198242Courtesy of SUBARU OF AMERICA, INC.
    6. Further press the ST2 downward and hold it for 5 seconds or more after the ST2 come all the way to the end, and then rectify the fuel injector seal.
      CAUTION:

      Be careful not to let the fuel injector seal get caught in the ST2 and the fuel injector groove. If it gets caught, repeat the procedure from the step   2 . 

      NOTE:

      If it is hard to press down the ST2, try to slowly press down the ST2 by shaking it side to side. 

      Preparation tool: 

      ST2: ADJUSTER (18271AA040)

      G13198243Courtesy of SUBARU OF AMERICA, INC.
    7. After installing the fuel injector seal, check the seal for scratches, crushed area, or dislocation from the groove.
      CAUTION:

      If scratches, crushed area, or dislocation from the groove is found in the fuel injector seal, repeat the procedure from the step   2 . 

      G13948331Courtesy of SUBARU OF AMERICA, INC.
  5. Install the new support disc and new O-ring.
    CAUTION:
    • If the tip of the fuel injector assembly is hit or the assembly is dropped, replace the fuel injector assembly with a new one. 
    • Check the O-ring seal groove of the fuel injector for foreign materials or damage. 
    • Be careful of the orientation of the support disc. 
    • Make sure that the installation order of the support disc and O-ring is correct. 
    • There should be no expansion or ride over at the support disc gap as shown in the figure. 
    G14600977Courtesy of SUBARU OF AMERICA, INC.
  6. Install a new decoupling.
    CAUTION:
    • If the tip of the fuel injector assembly is hit or the assembly is dropped, replace the fuel injector assembly with a new one. 
    • When installing the decoupling, the groove side (a) should face toward the fuel injector. 
    G13198246Courtesy of SUBARU OF AMERICA, INC.
  7. After assembling the parts, check that there is no foreign materials or damage on the fuel injector seal.
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