2004 SUBARU FORESTER ignition

IG(H4SO)-7
IGNITION
Spark Plug
3) Oil fouled:
Wet black deposits show excessive oil entrance
into combustion chamber through worn rings and
pistons or excessive clearance between valve
guides and stems. If the same condition remains
after repair, use a hotter plug.
4) Overheating:
White or light gray insulator with black or gray
brown spots and bluish burnt electrodes indicates
engine overheating. Moreover, the appearance re-
sults from incorrect ignition timing, loose spark
plugs, wrong selection of fuel, hotter range plug,
etc. It is advisable to replace with plugs having
colder heat range.
D: CLEANING
Clean the spark plugs in a sand blast type cleaner.
Avoid excessive blasting. Clean and remove the
carbon or oxide deposits, but do not wear away ce-
ramic insulator.
If deposits are too stubborn, replace the spark
plugs.
E: ADJUSTMENT
Correct it if the spark plug gap is measured with a
gap gauge, and it is necessary.
Spark plug gap: L
1.0 — 1.1 mm (0.039 — 0.043 in)
NOTE:
Replace with a new spark plug if this area (A) is
worn to “ball” shape.
IG-00026
IG-00027
IG-00028
L
(A)

IG(H4SO)-8
IGNITION
Ignition Coil & Ignitor Assembly
3. Ignition Coil & Ignitor Assem-
bly
A: REMOVAL
1) Disconnect the ground cable from battery.
2) Disconnect the spark plug cords from ignition
coil & ignitor assembly.
3) Disconnect the connector from ignition coil & ig-
nitor assembly.
4) Remove the ignition coil & ignitor assembly.
B: INSTALLATION
Install in the reverse order of removal.
Tightening torque:
6.4 N
⋅m (0.65 kgf-m, 4.7 ft-lb)
C: INSPECTION
Using the accurate tester, inspect the secondary
coil resistance, and replace if defective.
CAUTION:
 If the resistance is extremely low, this indi-
cates the presence of a short-circuit.
 Ignitor is integrated in coil. Therefore, prima-
ry coil resistance can not be measured.
Specified resistance:
[Secondary side]
Between (A) and (B)
12.8 k
Ω±15%
Between (C) and (D)
12.8 k
Ω±15%
Insulation between primary terminal and case: 100
MΩ or more.
FU-00009
IG-00043
IG-00044
IG-00044
IG-00045
(C)
(A)
(D)
(B)

IG(H4SO)-9
IGNITION
Spark Plug Cord
4. Spark Plug Cord
A: INSPECTION
Check for:
1) Damage to cords, deformation, burning or rust
formation of terminals
2) Resistance values of cords
Resistance value:
#1 cord: 5.6 — 10.6 k
Ω
#2 cord: 7.3 — 13.7 kΩ
#3 cord: 5.9 — 11.1 kΩ
#4 cord: 7.3 — 13.7 kΩ
IG-00031

IG(H4SO)-10
IGNITION
Spark Plug Cord

FUJI HEAVY INDUSTRIES LTD. G8080GE2
2004 FORESTER SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE SECTION 1
This service manual has been prepared
to provide SUBARU service personnel
with the necessary information and data
for the correct maintenance and repair
of SUBARU vehicles.
This manual includes the procedures
for maintenance, disassembling, reas-
sembling, inspection and adjustment of
components and diagnostics for guid-
ance of experienced mechanics.
Please peruse and utilize this manual
fully to ensure complete repair work for
satisfying our customers by keeping
their vehicle in optimum condition.
When replacement of parts during
repair work is needed, be sure to use
SUBARU genuine parts.
All information, illustration and specifi-
cations contained in this manual are
based on the latest product information
available at the time of publication
approval.FUEL INJECTION (FUEL SYSTEM) FU(H4SO)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICE)EC(H4SO)
INTAKE (INDUCTION) IN(H4SO)
MECHANICAL ME(H4SO)
EXHAUST EX(H4SO)
COOLING CO(H4SO)
LUBRICATION LU(H4SO)
SPEED CONTROL SYSTEM SP(H4SO)
IGNITION IG(H4SO)
STARTING/CHARGING SYSTEM SC(H4SO)
ENGINE (DIAGNOSTIC) EN(H4SO)

FUJI HEAVY INDUSTRIES LTD. G8080GE2
2004 FORESTER SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE SECTION 1
This service manual has been prepared
to provide SUBARU service personnel
with the necessary information and data
for the correct maintenance and repair
of SUBARU vehicles.
This manual includes the procedures
for maintenance, disassembling, reas-
sembling, inspection and adjustment of
components and diagnostics for guid-
ance of experienced mechanics.
Please peruse and utilize this manual
fully to ensure complete repair work for
satisfying our customers by keeping
their vehicle in optimum condition.
When replacement of parts during
repair work is needed, be sure to use
SUBARU genuine parts.
All information, illustration and specifi-
cations contained in this manual are
based on the latest product information
available at the time of publication
approval.FUEL INJECTION (FUEL SYSTEM) FU(H4SO)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICE)EC(H4SO)
INTAKE (INDUCTION) IN(H4SO)
MECHANICAL ME(H4SO)
EXHAUST EX(H4SO)
COOLING CO(H4SO)
LUBRICATION LU(H4SO)
SPEED CONTROL SYSTEM SP(H4SO)
IGNITION IG(H4SO)
STARTING/CHARGING SYSTEM SC(H4SO)
ENGINE (DIAGNOSTIC) EN(H4SO)

EN(H4SO)-2
ENGINE (DIAGNOSTIC)
Basic Diagnostics Procedure
1. Basic Diagnostics Procedure
A: PROCEDURE
1. ENGINE
Step Check Yes No
1 CHECK ENGINE START FAILURE.
1) Ask the customer when and how the trou-
ble occurred using the interview check list.
List for Interview.>
2) Start the engine.Does the engine start? Go to step 2.Inspection using
“Diagnostics for
Engine Starting
Failure”. EN(H4SO)-57,
Diagnostics for
Engine Starting
Fai lu r e.>
2 CHECK ILLUMINATION OF MALFUNCTION
INDICATOR LIGHT.Does malfunction indicator
light illuminate?Go to step 3.Inspection using
“General Diagnos-
tic Table”. EN(H4SO)-255,
INSPECTION,
General Diagnos-
tic Table.>
3 CHECK INDICATION OF DTC ON DISPLAY
1) Turn the ignition switch to OFF.
2) Connect the Subaru Select Monitor or the
OBD-II general scan tool to data link connec-
tor.
3) Turn the ignition switch to ON and the Sub-
aru Select Monitor or OBD-II general scan tool
switch to ON.
4) Read the DTC on the Subaru Select Moni-
tor or OBD-II general scan tool.Does the Subaru Select Moni-
tor or OBD-II general scan tool
indicate DTC?Record the DTC.
Repair the trouble
cause. EN(H4SO)-72, List
of Diagnostic Trou-
ble Code (DTC).>
Go to step 4.Repair the related
parts.
N
OTE:
If DTC is not shown
on display although
the engine warning
light illuminates, per-
form the diagnostics
of engine warning
light circuit or combi-
nation meter. to EN(H4SO)-47,
Malfunction Indica-
tor Light.>
4 PERFORM THE DIAGNOSIS.
1) Perform the Clear Memory Mode. EN(H4SO)-44, Clear Memory Mode.>
2) Perform the Inspection Mode. EN(H4SO)-37, Inspection Mode.>Does the Subaru Select Moni-
tor or OBD-II general scan tool
indicate DTC?Check on “Diag-
nostic Procedure
with Diagnostic
Trouble Code
(DTC)”
EN(H4SO)-78,
Diagnostic Proce-
dure with Diagnos-
tic Trouble Code
(DTC).>Finish the diagno-
sis.

EN(H4SO)-6
ENGINE (DIAGNOSTIC)
General Description
3. General Description
A: CAUTION
1) Airbag system wiring harness is routed near the
ECM, main relay and fuel pump relay.
CAUTION:
 All air bag system wiring harnesses and con-
nectors are yellow. Do not use the electrical
test equipment on these circuits.
 Be careful not to damage the Airbag system
wiring harness when servicing the ECM, TCM,
main relay and fuel pump relay.
2) Never connect the battery in reverse polarity.
 The ECM will be destroyed immediately.
 The fuel injector and other part will be damaged.
3) Do not disconnect the battery terminals while the
engine is running.
A large counter electromotive force will be generat-
ed in the generator, and this voltage may damage
electronic parts such as ECM, etc.
4) Before disconnecting the connectors of each
sensor and the ECM, be sure to turn the ignition
switch to OFF.
5) Poor contact has been identified as a primary
cause of this problem. Measure the voltage or re-
sistance of individual sensor or all electrical control
modules using a tapered pin with a diameter of less
than 0.64 mm (0.025 in). Do not insert the pin more
than 5 mm (0.20 in) into the part.
6) Remove the ECM from the located position after
disconnecting two cables on battery.
Otherwise, the ECM may be damaged.
CAUTION:
When replacing the ECM, be careful not to use
the wrong spec. ECM to avoid any damage on
the fuel injection system.
7) Connectors to each sensor in the engine com-
partment and the harness connectors on the en-
gine side and body side are all designed to be
waterproof. However, it is still necessary to take
care not to allow water to get into the connectors
when washing the vehicle, or when servicing the
vehicle on a rainy day.8) Use ECM mounting stud bolts as the grounding
point to body when measuring voltage and resis-
tance inside the passenger compartment.
9) Use engine ground terminal or engine proper as
the grounding point to body when measuring volt-
age and resistance in the engine compartment.
10) Use TCM mounting stud bolts as the grounding
point to body when measuring voltage and resis-
tance inside the passenger compartment.
11) Every MFI-related part is a precision part. Do
not drop them.
12) Observe the following cautions when installing
a radio in MFI equipped models.
CAUTION:
 The antenna must be kept as far apart as pos-
sible from the control unit. (The ECM is located
under the steering column, inside of the instru-
ment panel lower trim panel.)
(A) Stud bolt
(A) Stud bolt
EN-00001
(A)
EN-00153
EN-00154(A)