2004 SUBARU FORESTER fuel type

IG(H4SO)-6
IGNITION
Spark Plug
6) Remove the spark plugs with spark plug sock-
ets.
B: INSTALLATION
1. RH SIDE
Install in the reverse order of removal.
Tightening torque (Spark plug):
21 N
⋅m (2.1 kgf-m, 15.2 ft-lb)
NOTE:
The above torque should be only applied to new
spark plugs without oil on their threads.
In case their threads are lubricated, the torque
should be reduced by approx. 1/3 of the specified
torque in order to avoid over-stressing.
2. LH SIDE
Install in the reverse order of removal.
Tightening torque (Spark plug):
21 N
⋅m (2.1 kgf-m, 15.2 ft-lb)
NOTE:
The above torque should be only applied to new
spark plugs without oil on their threads.
In case their threads are lubricated, the torque
should be reduced by approx. 1/3 of the specified
torque in order to avoid over-stressing.
C: INSPECTION
Check the electrodes and inner and ceramic insu-
lator of plugs, noting the type of deposits and the
degree of electrode erosion.
1) Normal:
Brown to grayish-tan deposits and slight electrode
wear indicates correct spark plug heat range.
2) Carbon fouled:
Dry fluffy carbon deposits on insulator and elec-
trode are mostly caused by slow speed driving in
city, weak ignition, too rich fuel mixture, dirty air
cleaner, etc.
It is advisable to replace with plugs having hotter
heat range.
IG-00022
(A) Electrode gap
(B) Carbon accumulation or wear
(C) Cracks
(D) Damage
(E) Damaged gasket
IG-00023
(A)
(B)
(C)
(D)
(E)
IG-00024
IG-00025

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)

EN(H4SO)-7
ENGINE (DIAGNOSTIC)
General Description
 The antenna feeder must be placed as far
apart as possible from the ECM and MFI har-
ness.
 Carefully adjust the antenna for correct
matching.
 When mounting a large power type radio, pay
special attention to the three items above men-
tioned.
 Incorrect installation of the radio may affect
the operation of the ECM.
13) Before disconnecting the fuel hose, disconnect
the fuel pump connector and crank the engine for
more than five seconds to release pressure in the
fuel system. If engine starts during this operation,
run it until it stops.
14) Problems in the electronic-controlled automatic
transmission may be caused by failure of the en-
gine, the electronic control system, the transmis-
sion proper, or by a combination of these. These
three causes must be distinguished clearly when
performing diagnostics.
15) Diagnostics should be conducted by rotating
with simple, easy operations and proceeding to
complicated, difficult operations. The most impor-
tant thing in diagnostics is to understand the cus-
tomer’s complaint, and distinguish between the
three causes.
16) In AT models, do not continue the stall for more
than five seconds. (from closed throttle, fully open
throttle to stall engine speed.)
17) On the model with ABS, when performing driv-
ing test in jacked-up or lifted-up position, some-
times the warning light may be lit, but this is not a
malfunction of the system. The reason for this is the
speed difference between the front and rear
wheels. After diagnosis of engine control system,
perform the ABS memory clearance procedure of
self-diagnosis function.
B: INSPECTION
Before performing diagnostics, check the following
items which might affect engine problems:
1. BATTERY
1) Measure battery voltage and specific gravity of
electrolyte.
Standard voltage: 12 V
Specific gravity: Above 1.260
2) Check the condition of the main and other fuses,
and harnesses and connectors. Also check for
proper grounding.
2. ENGINE GROUND
Make sure the engine grounding terminal is proper-
ly connected to the engine.
C: NOTE
1. GENERAL DESCRIPTION
 On-board diagnosis (OBD) system detects and
indicates a fault in various inputs and outputs of the
complex electronic control. Malfunction indicator
light in the combination meter indicates occurrence
of a fault or trouble.
 Further, against such a failure or sensors as may
disable the drive, the fail-safe function is provided
to ensure the minimal driveability.
 The OBD system incorporated with the vehicles
within this engine family complies with Section
1968.1, California Code of Regulations (OBD-II
regulation). The OBD system monitors the compo-
nents and the system malfunction listed in Engine
Section which affects on emissions.
 When the system decides that a malfunction oc-
curs, malfunction indicator light illuminates. At the
same time of the malfunction indicator light illumi-
nation or blinking, the DTC and a freeze frame en-
gine conditions are stored into on-board computer.
 The OBD system stores freeze frame engine
condition data (engine load, engine coolant tem-
perature, fuel trim, engine speed and vehicle
speed, etc.) into on-board computer when it detects
a malfunction first.
 If the OBD system detects the various malfunc-
tions including the fault of fuel trim or misfire, the
OBD system first stores freeze frame engine condi-
tions about the fuel trim or misfire.
 When the malfunction does not occur again for
three consecutive driving cycles, malfunction indi-
cator light is turned off, but DTC remains at on-
board computer.
 The OBD-II system is capable of communication
with a general scan tool (OBD-II general scan tool)
formed by ISO 9141 CARB.
EN-00153

EN(H4SO)-30
ENGINE (DIAGNOSTIC)
Subaru Select Monitor
4. READ CURRENT DATA FOR ENGINE. (NORMAL MODE)
1) On the «Main Menu» display screen, select the {Each System Check} and press the [YES] key.
2) On the «System Selection Menu» display screen, select the {Engine} and press the [YES] key.
3) Press the [YES] key after the information of engine type was displayed.
4) On the «Engine Diagnosis» display screen, select the {Current Data Display/Save}, and then press the
[YES] key.
5) On the «Data Display Menu» display screen, select the {Data Display} and press the [YES] key.
6) Using the scroll key, scroll the display screen up or down until the desired data is shown.
 A list of the support data is shown in the following table.
Description Display Unit of measure
Battery voltage Battery Voltage V
Vehicle speed signal Meter vehicle speed km/h or MPH
Engine speed signal Engine speed rpm
Engine coolant temperature signal Engine coolant temperature°C or (°F)
Ignition timing signal Ignition timing deg
Throttle position signal Amount of intake air %
Throttle position signal Throttle Sensor Voltage V
Injection pulse width Fuel injection pulse width ms
Idle air control signal ISC Steps STEP
Engine load data Engine load %
Front oxygen (A/F) sensor resistance A/F sensor resistance value 1 ohm
Front oxygen (A/F) sensor output signal A/F sensor current value 1 —
Rear oxygen sensor output signalRear oxygen sensor voltage
valueV
Short term fuel trim A/F Compensation 1 %
Knock sensor signal Knock Correction deg
Atmospheric absolute pressure signal Atmospheric pressure mmHg, kPa, inHg or psi
Intake manifold relative pressure signal Mani. Relative Pressure mmHg, kPa, inHg or psi
Intake manifold absolute pressure signalIntake manifold absolute pres-
suremmHg, kPa, inHg or psi
A/F correction (short term fuel trim) by rear oxygen sensor A/F Compensation 3 %
Long term whole fuel trim A/F learning 1 %
Front oxygen (A/F) sensor heater current Front O2 heater current value A
Rear oxygen sensor heater current Rear O2 heater current value A
Canister purge control solenoid valve duty ratio CPC Valve Duty Ratio %
Fuel level signal Fuel level voltage V
Intake air temperature signal Intake air temperature°C or (°F)
Learned ignition timing Ignition learning value deg
EGR signal EGR Steps STEP
Ignition switch signal Ignition SW ON or OFF
Test mode connector signal Test mode signal ON or OFF
Neutral position switch signal Neutral SW ON or OFF
Air conditioning switch signal A/C SW ON or OFF
Air conditioning compressor signal A/C Compressor Signal ON or OFF
Radiator main fan relay signal Radiator fan relay 1 ON or OFF
Fuel pump relay signal Fuel pump relay ON or OFF
Knocking signal Knock signal ON or OFF
Radiator sub fan relay signal Radiator fan relay 2 ON or OFF
Power steering switch signal Power steering SW input signal ON or OFF
Engine torque control signal #1 AT coordinate request signal 1 ON or OFF
Engine torque control signal #2 AT coordinate request signal 2 ON or OFF

EN(H4SO)-32
ENGINE (DIAGNOSTIC)
Subaru Select Monitor
5. READ CURRENT DATA FOR ENGINE (OBD MODE)
1) On the «Main Menu» display screen, select the {Each System Check} and press the [YES] key.
2) On the «System Selection Menu» display screen, select the {Engine} and press the [YES] key.
3) Press the [YES] key after the information of engine type was displayed.
4) On the «Engine Diagnosis» display screen, select the {OBD system} and press the [YES] key.
5) On the «OBD Menu» display screen, select the {Current Data Display & Save}, and press the [YES] key.
6) On the «Data Display Menu» display screen, select the {Data Display} and press the [YES] key.
7) Using the scroll key, scroll the display screen up or down until the desired data is shown.
 A list of the support data is shown in the following table.
NOTE:
For detailed operation procedure, refer to the “SUBARU SELECT MONITOR OPERATION MANUAL”.
Description Display Unit of measure
Number of DTC Number of diagnosis code —
Condition of malfunction indicator light MI (MIL) ON or OFF
Monitoring test of misfire Misfire Monitoring Complete or incomplete
Monitoring test of fuel system Fuel System Diagnosis Complete or incomplete
Monitoring test of comprehensive component Component Diagnosis Complete or incomplete
Test of catalyst Catalyst diagnosis Complete or incomplete
Test of heating-type catalyst Heated catalyst diagnosis No support
Test of evaporative emission purge control system Evap. purge diagnosis Complete or incomplete
Test of secondary air system Secondary air diagnosis No support
Test of air conditioning system refrigerant A/C refrigerant diagnosis No support
Test of oxygen sensor O2 sensor diagnosis Complete or incomplete
Test of oxygen sensor heater O2 heater diagnosis Complete or incomplete
Test of EGR system EGR diagnosis —
Air fuel ratio control system for bank 1 Fuel System for bank 1 —
Engine load data Engine load %
Engine coolant temperature signal Engine coolant temperature°C or (°F)
Short term fuel trim by front oxygen (A/F) sensor Short term fuel trim B1 %
Long term fuel trim by front oxygen (A/F) sensor Long term fuel trim B1 %
Intake manifold absolute pressure signalIntake manifold absolute pres-
suremmHg, kPa, inHg or psi
Engine speed signal Engine speed rpm
Vehicle speed signal Meter vehicle speed km/h or MPH
Ignition timing advance for #1 cylinder Ignition timing adv. #1°
Intake air temperature signal Intake air temperature°C or (°F)
Amount of intake air Amount of intake air g/s
Throttle position signal Throttle valve angle %
Rear oxygen sensor output signal O2 sensor #12 V
Air fuel ratio correction by rear oxygen sensor Short term fuel trim #12 %
On-board diagnostic system OBD system —
Oxygen sensor #11 O2 sensor #11 With support
Oxygen sensor #12 O2 sensor #12 With support
A/F sensor #11 A/F sensor #11 —

EN(H4SO)-33
ENGINE (DIAGNOSTIC)
Subaru Select Monitor
6. READ FREEZE FRAME DATA FOR ENGINE. (OBD MODE)
1) On the «Main Menu» display screen, select the {Each System Check} and press the [YES] key.
2) On the «System Selection Menu» display screen, select the {Engine} and press the [YES] key.
3) Press the [YES] key after the information of engine type was displayed.
4) On the «Engine Diagnosis» display screen, select the {OBD System} and press the [YES] key.
5) On the «OBD Menu» display screen, select the {Freeze Frame Data} and press the [YES] key.
 A list of the support data is shown in the following table.
NOTE:
For detailed operation procedure, refer to the SUBARU SELECT MONITOR OPERATION MANUAL.
Description Display Unit of measure
DTC of freeze frame data Freeze frame data DTC
Air fuel ratio control system for bank 1 Fuel system for Bank 1 ON or OFF
Engine load data Engine load %
Engine coolant temperature signal Engine coolant temperature°C or (°F)
Short term fuel trim by front oxygen (A/F) sensor Short term fuel trim B1 %
Long term fuel trim by front oxygen (A/F) sensor Long term fuel trim B1 %
Intake manifold absolute pressure signalIntake manifold absolute pres-
suremmHg, kPa, inHg or psi
Engine speed signal Engine speed rpm
Vehicle speed signal Meter vehicle speed km/h or MPH

EN(H4SO)-34
ENGINE (DIAGNOSTIC)
Subaru Select Monitor
7. LED OPERATION MODE FOR ENGINE
1) On the «Main Menu» display screen, select the {Each System Check} and press the [YES] key.
2) On the «System Selection Menu» display screen, select the {Engine} and press the [YES] key.
3) Press the [YES] key after the information of engine type was displayed.
4) On the «Engine Diagnosis» display screen, select the {Current Data Display/Save}, and then press the
[YES] key.
5) On the «Data Display Menu» display screen, select the {Data & LED Display} and press the [YES] key.
6) Using the scroll key, scroll the display screen up or down until the desired data is shown.
 A list of the support data is shown in the following table.
NOTE:
For detailed operation procedure, refer to the “SUBARU SELECT MONITOR OPERATION MANUAL”.
Description Display Message LED “ON” requirements
Ignition switch signal Ignition SW ON or OFF When ignition switch is ON
Test mode connector signal Test mode signal ON or OFF When test mode connector is connected.
Neutral position switch signal Neutral SW ON or OFF When neutral position signal is entered.
Air conditioning switch signal A/C SW ON or OFF When air conditioning switch is ON
Air conditioning relay signal A/C Compressor Relay ON or OFF When air conditioning relay is in function.
Radiator main fan relay signal Radiator fan relay 1 ON or OFF When radiator main fan relay is in function.
Fuel pump relay signal Fuel pump relay ON or OFF When fuel pump relay is in function.
Knocking signal Knock signal ON or OFF When knocking signal is input.
Radiator sub fan relay signal Radiator fan relay 2 ON or OFF When radiator sub fan relay is in function.
Engine torque control signal #1 AT coordinate request signal 1 ON or OFFWhen engine torque control signal 1 is
entered
Engine torque control signal #2 AT coordinate request signal 2 ON or OFFWhen engine torque control signal 2 is
entered
Engine torque control permission
signalAT coordinate permission sig-
nalON or OFFWhen engine torque control permission sig-
nal is entered.
Front oxygen (A/F) sensor rich sig-
nalFront O2 Rich Signal #1 ON or OFFWhen front oxygen (A/F) sensor mixture ratio
is rich.
Rear oxygen sensor rich signal RrO2 monitor ON or OFFWhen rear oxygen sensor mixture ratio is
rich.
Starter switch signal Starter SW ON or OFF When starter switch signal is entered.
Idle switch signal Idle Switch Signal ON or OFF When idle switch signal is entered.
Crankshaft position sensor signal Crankshaft position signal ON or OFFWhen crankshaft position sensor signal is
input.
Camshaft position sensor signal Camshaft position signal ON or OFFWhen camshaft position sensor signal is
entered.

FU(H4DOTC)-2
FUEL INJECTION (FUEL SYSTEM)
General Description
1. General Description
A: SPECIFICATION
Fuel tankCapacity 602 (15.9 US gal, 13.2 Imp gal)
Location Under rear seat
Fuel pumpType Impeller
Shutoff discharge pressure
450 — 677 kPa (4.59 — 6.9 kg/cm
2, 65.27 — 98.2 psi)
Discharge flowMore than 1302 (34.3 US gal, 28.6 Imp gal)/h
[12 V at 300 kPa (3.06 kg/cm
2, 43.5 psi)]
Fuel filterCartridge type