Subaru Legacy 2003 Service Manual page 562

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Step
7 CHECK FUEL PRESSURE.
Warning:
•Place "NO FIRE" signs near the working
area.
•Be careful not to spill fuel on the floor.
1) Release fuel pressure.
(1) Disconnect connector from fuel pump
relay.
(2) Start the engine and run it until it stalls.
(3) After the engine stalls, crank it for five
more seconds.
(4) Turn ignition switch to OFF.
2) Connect connector to fuel pump relay.
3) Disconnect fuel delivery hose from fuel fil-
ter, and connect fuel pressure gauge.
4) Install fuel filler cap.
5) Start the engine and idle while gear position
is neutral.
6) Measure fuel pressure while disconnecting
pressure regulator vacuum hose from
intake manifold.
Is the measured value within the specified
range?
Warning:
Before removing fuel pressure gauge, re-
lease fuel pressure.
NOTE:
If fuel pressure does not increase, squeeze fuel
return hose 2 to 3 times, then measure fuel
pressure again.
8 CHECK FUEL PRESSURE.
After connecting pressure regulator vacuum
hose, measure fuel pressure.
Is the measured value within the specified
range?
Warning:
Before removing fuel pressure gauge, re-
lease fuel pressure.
NOTE:
•If fuel pressure does not increase, squeeze
fuel return hose 2 to 3 times, then measure
fuel pressure again.
•If out of specification as measured at this
step, check or replace pressure regulator and
pressure regulator vacuum hose.
Value
284 — 314 kPa (2.9 — 3.2 kg/
2
cm , 41 — 46 psi)
206 — 235 kPa (2.1 — 2.4 kg/
2
cm , 30 — 34 psi)
EN(H4SO)-165
ENGINE (DIAGNOSTICS)
Yes
Go to step 8. Repair the follow-
ing items.
Fuel pressure too
high
• Clogged fuel
return line or
bent hose
Fuel pressure too
low
• Improper fuel
pump discharge
• Clogged fuel
supply line
Go to step 9. Repair the follow-
ing items.
Fuel pressure too
high
• Faulty pres-
sure regulator
• Clogged fuel
return line or
bent hose
Fuel pressure too
low
• Faulty pres-
sure regulator
• Improper fuel
pump discharge
• Clogged fuel
supply line
No