Subaru FORESTER 2001 Service Manual page 318

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
No.
1 CHECK ANY OTHER DTC ON DISPLAY.
2 CHECK AIR INTAKE SYSTEM.
1) Turn ignition switch to ON.
2) Start engine, and idle it.
3) Check the following items.
¼ Loose installation of intake manifold, idle air
control solenoid valve and throttle body
¼ Cracks of intake manifold gasket, idle air
control solenoid valve gasket and throttle
body gasket
¼ Disconnections of vacuum hoses
3 CHECK THROTTLE CABLE.
4 CHECK AIR BY-PASS LINE.
1) Turn ignition switch to OFF.
2) Remove idle air control solenoid valve from
throttle body. <Ref. to FU(DOHC TURBO)-36,
Idle Air Control Solenoid Valve.>
3) Confirm that there are no foreign particles
in by-pass air line.
Step
Does the Subaru Select
Monitor or OBD-II general
scan tool indicate DTC
P0506, P0507, P0508,
P0509 or P1142?
Is there a fault in air intake
system?
Does throttle cable have
play for adjustment?
Are foreign particles in by-
pass air line?
EN(DOHC TURBO)-317
Check Yes
Inspect DTC
P0506, P0507,
P0508, P0509 or
P1142 using "List
of Diagnostic
Trouble Code
(DTC)". <Ref. to
EN(DOHC
TURBO)-82, List
of Diagnostic
Trouble Code
(DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0507.
Repair air suction
and leaks.
Go to step 4.
Remove foreign
particles from by-
pass air line.
Engine (Diagnostics)
No
Go to step 2.
Go to step 3.
Adjust throttle
cable. <Ref. to
SP-12, Accelera-
tor Control
Cable.>
Replace idle air
control solenoid
valve. <Ref. to
FU(DOHC
TURBO)-36, Idle
Air Control Sole-
noid Valve.>