Page 2013 of 2870

FUJI HEAVY INDUSTRIES LTD. G8080GE4
2004 FORESTER SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE SECTION 3
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(H4DOTC 2.5)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICE)EC(H4DOTC 2.5)
INTAKE (INDUCTION) IN(H4DOTC 2.5)
MECHANICAL ME(H4DOTC 2.5)
EXHAUST EX(H4DOTC 2.5)
COOLING CO(H4DOTC 2.5)
LUBRICATION LU(H4DOTC 2.5)
SPEED CONTROL SYSTEM SP(H4DOTC 2.5)
IGNITION IG(H4DOTC 2.5)
STARTING/CHARGING SYSTEM SC(H4DOTC 2.5)
ENGINE (DIAGNOSTIC) EN(H4DOTC 2.5)
Page 2018 of 2870

FUJI HEAVY INDUSTRIES LTD. G8080GE4
2004 FORESTER SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE SECTION 3
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(H4DOTC 2.5)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICE)EC(H4DOTC 2.5)
INTAKE (INDUCTION) IN(H4DOTC 2.5)
MECHANICAL ME(H4DOTC 2.5)
EXHAUST EX(H4DOTC 2.5)
COOLING CO(H4DOTC 2.5)
LUBRICATION LU(H4DOTC 2.5)
SPEED CONTROL SYSTEM SP(H4DOTC 2.5)
IGNITION IG(H4DOTC 2.5)
STARTING/CHARGING SYSTEM SC(H4DOTC 2.5)
ENGINE (DIAGNOSTIC) EN(H4DOTC 2.5)
Page 2021 of 2870

FUJI HEAVY INDUSTRIES LTD. G8080GE4
2004 FORESTER SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE SECTION 3
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(H4DOTC 2.5)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICE)EC(H4DOTC 2.5)
INTAKE (INDUCTION) IN(H4DOTC 2.5)
MECHANICAL ME(H4DOTC 2.5)
EXHAUST EX(H4DOTC 2.5)
COOLING CO(H4DOTC 2.5)
LUBRICATION LU(H4DOTC 2.5)
SPEED CONTROL SYSTEM SP(H4DOTC 2.5)
IGNITION IG(H4DOTC 2.5)
STARTING/CHARGING SYSTEM SC(H4DOTC 2.5)
ENGINE (DIAGNOSTIC) EN(H4DOTC 2.5)
Page 2024 of 2870

FUJI HEAVY INDUSTRIES LTD. G8080GE4
2004 FORESTER SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE SECTION 3
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(H4DOTC 2.5)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICE)EC(H4DOTC 2.5)
INTAKE (INDUCTION) IN(H4DOTC 2.5)
MECHANICAL ME(H4DOTC 2.5)
EXHAUST EX(H4DOTC 2.5)
COOLING CO(H4DOTC 2.5)
LUBRICATION LU(H4DOTC 2.5)
SPEED CONTROL SYSTEM SP(H4DOTC 2.5)
IGNITION IG(H4DOTC 2.5)
STARTING/CHARGING SYSTEM SC(H4DOTC 2.5)
ENGINE (DIAGNOSTIC) EN(H4DOTC 2.5)
Page 2025 of 2870

ENGINE (DIAGNOSTIC)
EN(H4DOTC 2.5)
Page
1. Basic Diagnostics Procedure ......................................................................2
2. Check List for Interview ...............................................................................3
3. General Description ....................................................................................5
4. Electrical Component Location ...................................................................8
5. Engine Control Module (ECM) I/O Signal .................................................17
6. Engine Condition Data ..............................................................................22
7. Data Link Connector .................................................................................23
8. OBD-II General Scan Tool ........................................................................24
9. Subaru Select Monitor...............................................................................27
10. Read Diagnostic Trouble Code (DTC) ......................................................34
11. Inspection Mode ........................................................................................35
12. Drive Cycle ................................................................................................40
13. Clear Memory Mode..................................................................................42
14. Compulsory Valve Operation Check Mode ...............................................43
15. Malfunction Indicator Light ........................................................................45
16. Diagnostics for Engine Starting Failure .....................................................54
17. List of Diagnostic Trouble Code (DTC) .....................................................65
18. Diagnostic Procedure with Diagnostic Trouble Code (DTC) .....................70
19. General Diagnostic Table........................................................................258
Page 2026 of 2870

EN(H4DOTC 2.5)-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.
Check List for Interview.>
2) Start the engine.Does the engine start? Go to step 2.Inspection using
“Diagnostics for
Engine Start Fail-
ure”.
EN(H4DOTC 2.5)-
54, 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(H4DOTC 2.5)-
258, General Diag-
nostic 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(H4DOTC 2.5)-
65, List of Diag-
nostic Trouble
Code (DTC).> Go
to step 4.Repair the related
parts.
N
OTE:
If DTC is not shown
on display although
the malfunction in-
dicator light illumi-
nates, perform the
diagnostics for mal-
function indicator
light circuit or com-
bination meter.
EN(H4DOTC 2.5)-
45, Malfunction In-
dicator Light.>
4 PERFORM THE DIAGNOSIS.
1) Perform clear memory mode.
EN(H4DOTC 2.5)-42, Clear Memory Mode.>
2) Perform the “INSPECTION MODE”.
to EN(H4DOTC 2.5)-35, Inspection Mode.>Does the Subaru Select Moni-
tor or OBD-II general scan tool
indicate DTC?Check on “Diag-
nostic Chart with
Diagnostic Trou-
ble Code (DTC)”.
EN(H4DOTC 2.5)-
70, Diagnostic
Procedure with
Diagnostic Trou-
ble Code (DTC).>Finish the diagno-
sis.
Page 2027 of 2870

EN(H4DOTC 2.5)-3
ENGINE (DIAGNOSTIC)
Check List for Interview
2. Check List for Interview
A: INSPECTION
1. CHECK LIST No. 1
Check the following items when problem has occurred.
NOTE:
Use copies of this page for interviewing customers.
Customer’s name Engine No.
Date of sale Fuel brand
Date of repair
Odometer readingkm
V.I.N.miles
Weather❏ Fine
❏ Cloudy
❏ Rainy
❏ Snowy
❏ Va r i o u s / O t h e r s :
Ambient air temperature°C (°F)
❏ Hot
❏ War m
❏ Cool
❏ Cold
Place❏ Highway
❏ Suburbs
❏ Inner city
❏ Uphill
❏ Downhill
❏ Rough road
❏ Others:
Engine temperature❏ Cold
❏ War ming-up
❏ After warming-up
❏ Any temperature
❏ Others:
Engine speed rpm
Vehicle speed km/h (MPH)
Driving conditions❏ Not affected
❏ At starting
❏ While idling
❏ At racing
❏ While accelerating
❏ While cruising
❏ While decelerating
❏ While turning (RH/LH)
Headlight❏ ON / ❏ OFF Rear defogger❏ ON / ❏ OFF
Blower❏ ON / ❏ OFF Radio❏ ON / ❏ OFF
A/C compressor❏ ON / ❏ OFF CD/Cassette❏ ON / ❏ OFF
Radiator fan❏ ON / ❏ OFF Car phone❏ ON / ❏ OFF
Fr o nt wi pe r❏ ON / ❏ OFF CB❏ ON / ❏ OFF
Rear Wiper❏ ON / ❏ OFF
Page 2028 of 2870

EN(H4DOTC 2.5)-4
ENGINE (DIAGNOSTIC)
Check List for Interview
2. CHECK LIST No. 2
Check the following items about the vehicle’s state when malfunction indicator light turns on.
NOTE:
Use copies of this page for interviewing customers.
a) Other warning lights or indicators turn on. ❏ Ye s / ❏ No
❏ Low fuel warning light
❏ Charge indicator light
❏ AT diagnostic indicator light
❏ ABS Warning Light
❏ Oil pressure indicator light
b) Fuel level
Lack of gasoline: ❏ Yes / ❏ No
Indicator position of fuel gauge:
Experienced running out of fuel: ❏ Ye s / ❏ No
c) Intentional connecting or disconnecting of harness connectors or spark plug cords: ❏ Yes / ❏ No
What:
d) Intentional connecting or disconnecting of hoses: ❏ Ye s / ❏ No
What:
e) Installing of other parts except genuine parts: ❏ Ye s / ❏ No
What:
Where:
f) Occurrence of noise: ❏ Yes / ❏ No
From where:
What kind:
g) Occurrence of smell: ❏ Yes / ❏ No
From where:
What kind:
h) Intrusion of water into engine compartment or passenger compartment: ❏ Yes / ❏ No
i) Troubles occurred
❏ Engine does not start
❏ Engine stalls during idling
❏ Engine stalls while driving
❏ Engine speed decreases
❏ Engine speed does not decrease
❏ Rough idling
❏ Poor acceleration
❏ Back fire
❏ After fire
❏ Does not shift
❏ Excessive shift shock