Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2020 Subaru WRX BaseFACTORY OEM SERVICE PROCEDURE
Fuel Injector: Replacement
CAUTION:
- Perform work without using gloves.
- Always use the ST when installing the injector seal.
| ST | 18683AA000 | INJECTOR SEAL INSTALLER |
- Using a pair of nippers, cut off the injector seal by pinching it.CAUTION: Be careful not to damage the fuel injector.
- Remove the O-ring and backup ring from the fuel injector.
- Attach the seal guide A to the fuel injector.NOTE: Two types of seal guides are provided. So, do not mix up the type to be used.
- Set the injector seal to the injector seal installer.
- Push in the injector seal installer slowly in the direction of the arrow, and attach the injector seal to the fuel injector.CAUTION:
- Insert it so that the injector seal is installed straight.
- Be careful that the injector seal does not go beyond the fuel injector groove.
- While rotating the injector seal adjuster to left and right by 90 degrees for each side, slowly insert it all the way.NOTE:
- Apply a thin coat of gasoline to the injector seal and injector seal adjuster.
- With the injector seal adjuster fully inserted, rotate it to left and right approx. ten times by 90 degrees for each side to normalize the injector seal.
- Attach the seal guide B to the fuel injector.NOTE: Two types of seal guides are provided. So, do not mix up the type to be used.
- Set the injector seal to the injector seal installer.
- Push in the injector seal installer slowly in the direction of the arrow, and attach the injector seal to the fuel injector.CAUTION:
- Insert it so that the injector seal is installed straight.
- Be careful that the injector seal does not go beyond the fuel injector groove.
- While rotating the injector seal adjuster to left and right by 90 degrees for each side, slowly insert it all the way.NOTE:
- Apply a thin coat of gasoline to the injector seal and injector seal adjuster.
- With the injector seal adjuster fully inserted, rotate it to left and right approx. ten times by 90 degrees for each side to normalize the injector seal.
- Attach two backup rings and O-ring to the fuel injector.NOTE: Use new backup rings and O-ring.
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
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