Fuel Pressure: Inspection

WARNING: This page is about a different variant/trim than selected.

WARNING: Before removing the fuel pressure gauge, release the fuel pressure.

NOTE: When the fuel pressure is out of specification, check or replace the pressure regulator and pressure regulator vacuum hose.

Remove the collector cover.
Release the fuel pressure. < Ref. to RELEASING OF FUEL PRESSURE , PROCEDURE, Fuel. >
Open the fuel filler flap lid, and remove the fuel filler cap.
Disconnect the fuel delivery hose and connect fuel pressure gauge.
Remove the fuse of fuel pump from main fuse box.

Fig 1: Removing Fuse Of Fuel Pump From Main Fuse Box
Courtesy of SUBARU OF AMERICA, INC.
Start the engine.
Measure the fuel pressure while disconnecting pressure regulator vacuum hose from intake manifold.
Fuel pressure:

Standard: 284 - 314 kPa (2.9 - 3.2 kgf/cm ² , 41 - 46psi)

Fig 2: Measuring Fuel Pressure
Courtesy of SUBARU OF AMERICA, INC.
After connecting the pressure regulator vacuum hose, measure the fuel pressure.

Fuel pressure:

Standard: 230 - 260 kPa (2.35 - 2.65 kgf/cm ² , 33 - 38 psi)

NOTE: The fuel pressure gauge registers 10 to 20 kPa (0.1 to 0.2 kgf/cm² , 1 to 3 psi) higher than standard values during high-altitude operations.