Fuel Pressure: Inspection

WARNING: This page is about a different car, the 2022 Subaru WRX. However, it is still accessible from the selected car via links, so may be relevant.

Release the fuel pressure. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FUEL>PROCEDURE>RELEASING OF FUEL PRESSURE
Open the fuel filler lid and remove the fuel filler cap.
NOTE:
This operation is required to release the inner pressure of the fuel tank.

Disconnect the fuel delivery tube from the fuel pipe assembly, and connect the fuel pressure gauge.

CAUTION:

Be careful not to spill fuel.
Catch the fuel from the tubes using a container or cloth.

Remove the fuel delivery tube clamp from the fuel delivery tube.

Courtesy of SUBARU OF AMERICA, INC.

Disconnect the quick connector on the fuel delivery tube from the fuel pipe assembly.

NOTE:

Disconnect the quick connector as shown in the figure.

Courtesy of SUBARU OF AMERICA, INC.

Courtesy of SUBARU OF AMERICA, INC.

Connect the fuel pressure gauge with ST1 and ST2.

CAUTION:

Check that there is no damage or dust on the quick connector. If necessary, clean the seal surface of the pipe.
When connecting the quick connector with slider, make sure to insert it all the way in before locking the slider.
When it is difficult to lock the slider, check that the connector is fully inserted.
After locking the slider, pull the quick connector itself to the disconnecting direction, and then push to the connecting direction in order to confirm secure connection. Always make sure to perform this confirmation ending up with a pushing in.

NOTE:

ST1 is a SUBARU genuine part.

When connecting the ST2 to the quick connector on the fuel delivery tube, connect it as shown in the figure.

Courtesy of SUBARU OF AMERICA, INC.

Preparation tool:

ST1: FUEL HOSE (42075AG690)

ST2: FUEL PIPE ADAPTER (18471AA000)

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Start the engine, and check the fuel pressure.
NOTE:
- The fuel pressure gauge reading becomes 10 - 20 kPa (0.1 - 0.2 kg/cm ² , 1 - 3 psi) higher than standard values during high-altitude operations.
- Check or replace the fuel pump and fuel delivery line if the fuel pressure is out of the standard.
Fuel pressure:

Standard

340 - 400 kPa (3.5 - 4.1 kg/cm² , 49 - 58 psi)

After inspection, install the related parts in the reverse order of removal.

CAUTION:

Before removing the fuel pressure gauge, release the fuel pressure.
Be careful not to spill fuel.
Catch the fuel from hoses and tubes using a container or cloth.
Check that there is no damage or dust on the quick connector. If necessary, clean the seal surface of the pipe.
When connecting the quick connector with slider, make sure to insert it all the way in before locking the slider.
When it is difficult to lock the slider, check that the connector is fully inserted.
After locking the slider, pull the quick connector itself to the disconnecting direction, and then push to the connecting direction in order to confirm secure connection. Always make sure to perform this confirmation ending up with a pushing in.

NOTE:

When disconnecting the ST1, install the ST2 to the fuel pipe assembly, and press the ST2 in the direction of arrow to disconnect the quick connector on the ST1.
Preparation tool:

ST2: QUICK CONNECTOR RELEASE (42099AE000)

Courtesy of SUBARU OF AMERICA, INC.

Disconnect the quick connector on the fuel delivery tube as shown in the figure.

Courtesy of SUBARU OF AMERICA, INC.

Connect the quick connector on the fuel delivery tube as shown in the figure.

Courtesy of SUBARU OF AMERICA, INC.