engine coolant SUBARU FORESTER 2004 Service Repair Manual

FU(H4DOTC 2.5)-15
FUEL INJECTION (FUEL SYSTEM)
Intake Manifold
(6) Place the power steering pump on the right
side wheel apron.
12) Disconnect the emission hose from the PCV
valve.
13) Disconnect the engine coolant hoses from the
throttle body.
14) Disconnect the brake booster hose.15) Disconnect the pressure hose from the intake
duct.
16) Disconnect the engine harness connectors
from the bulkhead harness connectors.
17) Disconnect the connectors from the engine cool-
ant temperature sensor (A), oil pressure switch (B)
and crankshaft position sensor (C).
FU-00021
FU-00022
FU-01074
FU-00023
FU-00024
FU-00025
FU-00026
(A)
(B)
(C)
FU-00027

FU(H4DOTC 2.5)-18
FUEL INJECTION (FUEL SYSTEM)
Intake Manifold
 LH SIDE
8) Connect the engine harness connector to the
bulkhead harness connectors.
9) Connect the brake booster vacuum hose.10) Connect the engine coolant hoses to the throt-
tle body.
11) Connect the emission hose to the PCV valve.
12) Connect the pressure hose to the intake duct.
13) Install the power steering pump.
(1) Install the reservoir tank on the bracket.
FU-01310
(A)
FU-00025
FU-00026
FU-00023
FU-01074
FU-00022
FU-00024
FU-00020

FU(H4DOTC 2.5)-19
FUEL INJECTION (FUEL SYSTEM)
Intake Manifold
(2) Connect the connector to the power steering
pump switch.
(3) Install the power steering pump, and tighten
the bolts.
Tightening torque:
22 N·m (2.2 kgf-m, 15.9 ft-lb)
(4) Install the power steering pipe brackets on
the intake manifold RH.
(5) Install the front side V-belt. ME(H4DOTC)-52, INSTALLATION, V-belt.>
14) Install the coolant filler tank. 42, INSTALLATION, Coolant Filler Tank.>
15) Install the intercooler. 11, INSTALLATION, Intercooler.>
16) Install the air cleaner element.
17) Install the air cleaner upper cover and air intake
duct as a unit. TION, Air Cleaner.>18) Connect the connector to the fuel pump relay.
19) Connect the battery ground cable to battery.
20) Lift up the vehicle.
21) Install the under cover.
22) Fill the engine coolant. FILLING OF ENGINE COOLANT, REPLACE-
MENT, Engine Coolant.>
C: DISASSEMBLY
1) Remove the fuel pipe protector RH.
2) Remove the engine ground terminal from the in-
take manifold.
FU-00017
FU-00019
FU-00018
ME-00649
FU-01040
FU-01041
FU-01042

FU(H4DOTC 2.5)-26
FUEL INJECTION (FUEL SYSTEM)
Engine Coolant Temperature Sensor
4. Engine Coolant Temperature
Sensor
A: REMOVAL
1) Disconnect the ground cable from battery.
2) Remove the generator. REMOVAL, Generator.>
3) Drain the engine coolant. DRAINING OF ENGINE COOLANT, REPLACE-
MENT, Engine Coolant.>
4) Disconnect the connector from the engine cool-
ant temperature sensor.
5) Remove the engine coolant temperature sensor.
B: INSTALLATION
Install in the reverse order of removal.
Tightening torque:
18 N·m (1.8 kgf-m, 13.3 ft-lb)
FU-00009
FU-00055

EN(H4DOTC 2.5)-6
ENGINE (DIAGNOSTIC)
General Description
13) 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.
14) 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 ground terminal is properly
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.
 The OBD-II diagnostics procedure is different
from the usual diagnosis procedure. When trouble-
shooting the OBD-II models, connect Subaru Se-
lect Monitor or the OBD-II general scan tool to the
vehicle.
EN-01201

EN(H4DOTC 2.5)-7
ENGINE (DIAGNOSTIC)
General Description
2. ENGINE AND EMISSION CONTROL SYS-
TEM
 MFI system is a system that supplies the opti-
mum air-fuel mixture to the engine for all the vari-
ous operating conditions through the use of the
latest electronic technology.
With this system fuel, which is pressurized at a con-
stant pressure, is injected into the intake air pas-
sage of the cylinder head. The injection quantity of
fuel is controlled by an intermittent injection system
where the electro-magnetic injection valve (fuel in-
jector) opens only for a short period of time, de-
pending on the quantity of air required for one cycle
of operation. In actual operation, the injection quan-
tity is determined by the duration of an electric sig-nal applied to the fuel injector and this permits
simple, yet highly precise metering of the fuel.
 Further, all the operating conditions of the engine
are converted into electric signals, and this results
in additional features of the system, such as large
improved adaptability, easier addition of compen-
sating element, etc.
The MFI system also has the following features:
 Reduced emission of harmful exhaust gases.
 Reduced in fuel consumption.
 Increased engine output.
 Superior acceleration and deceleration.
 Excellent engine start and warm-up perfor-
mance by the correction of engine coolant tem-
perature and intake air temperature.
D: PREPARATION TOOL
ILLUSTRATION TOOL NUMBER DESCRIPTION REMARKS
24082AA230
(Newly adopted tool)CARTRIDGE Troubleshooting for electrical system.
22771AA030 SUBARU SELECT
MONITOR KITTroubleshooting for electrical system.
 English: 22771AA030 (Without printer)
 German: 22771AA070 (Without printer)
 French: 22771AA080 (Without printer)
 Spanish: 22771AA090 (Without printer)
ST24082AA230
ST22771AA030

EN(H4DOTC 2.5)-9
ENGINE (DIAGNOSTIC)
Electrical Component Location
 SENSOR
(1) Manifold absolute pressure sen-
sor(3) Electronic throttle control (7) Mass air flow and intake air tem-
perature sensor
(4) Knock sensor
(2) Engine coolant temperature sen-
sor(5) Camshaft position sensor (8) Tumble generator valve position
sensor
(6) Crankshaft position sensor
EN-02008
(1)
(7) (6) (4) (8)(2)
(3)(5)

EN(H4DOTC 2.5)-17
ENGINE (DIAGNOSTIC)
Engine Control Module (ECM) I/O Signal
5. Engine Control Module (ECM) I/O Signal
A: ELECTRICAL SPECIFICATION
DESCRIPTION Connector No. Terminal No.Signal (V)
NOTE
Ignition SW ON
(engine OFF)Engine ON
(Idling)
Crank-
shaft posi-
tion sensorSignal (+) B135 10 0−7 — +7 Waveform
Signal (−) B135 22 0 0 —
Shield B135 31 0 0 —
Rear oxy-
gen sensorSignal B137 25 0 0 — 0.9 —
Shield B137 31 0 0 —
GND
(sensors)B136 35 0 0 —
Fr o nt ox y-
gen (A/F)
sensor
heaterSignal 1 B134 3 0 — 1.0 — Waveform
Signal 2 B134 2 0 — 1.0 — Waveform
Rear oxygen sensor
heater signalB135 2 0 — 1.0 — Waveform
Engine
coolant
tempera-
ture sen-
sorSignal B136 14 1.0 — 1.4 1.0 — 1.4 After engine is warmed-up.
GND
(sensors)B136 35 0 0 After engine is warmed-up.
Vehicle speed signal B135 26 0 or 5 0 or 5“5” and “0” are repeatedly dis-
played when vehicle is driven.
Air flow
sensorSignal B136 23 — 0.3 — 4.5 —
Shield B136 32 0 0 —
GND B136 31 0 0 —
Intake air temperature
sensor signalB136 13 0.3 — 4.6 0.3 — 4.6 —
Exhaust
gas tem-
perature
sensorSignal B136 24 — — —
GND
(sensors)B136 35 0 0 —
EN-01812
B134
5 6 7
8 21
9 43
10
24 2223 2511 12 13 14 15
26 27
28 16 17
18 19 20 21
33 34 29
32 3031
B136
5 6
7 8 21
9 43
10
24 2223 2511 12 13
14 15
26 27
28 16
17 18 19 20 21
33 3429
3230
31 35
B135
5 6 7
8 21
9 43
10
24 2223 2511 12 13 14 15
26 27
28 16 17 18 19
20 21
29 30 31 32 33 34 35
B137
5 6 7
8 21
9 43
10
22 2311 12 13 14 15
24 25
26 16 17
18 19 20 21
27 28 29 30 31
To
To To
To

EN(H4DOTC 2.5)-25
ENGINE (DIAGNOSTIC)
OBD-II General Scan Tool
2. MODE $01 (CURRENT POWERTRAIN DIAGNOSTIC DATA)
Refers to data denoting the current operating condition of analog input/output, digital input/output and/or the
powertrain system.
A list of the support data and PID (Parameter Identification) codes are shown in the following table.
NOTE:
Refer to OBD-II general scan tool manufacturer’s instruction manual to access generic OBD-II PIDs (MODE
$01).
3. MODE $02 (POWERTRAIN FREEZE FRAME DATA)
Refers to data denoting the operating condition when trouble is sensed by the on-board diagnosis system.
A list of the support data and PID (Parameter Identification) codes are shown in the following table.
NOTE:
Refer to OBD-II general scan tool manufacturer’s instruction manual to access freeze frame data (MODE
$02).
PID Data Unit of measure
01Number of emission-related powertrain DTC, malfunction indicator light status and diagnosis
support information—
03 Fuel system control status—
04 Calculated engine load value%
05 Engine coolant temperature°C
06 Short term fuel trim%
07 Long term whole fuel trim%
0B Intake manifold absolute pressure kPa, mmHg
0C Engine revolutionrpm
0D Vehicle speedkm/h
0E Ignition timing advance°
0F Intake air temperature°C
10 Air flow rate of mass air flow sensor g/sec
11 Throttle valve absolute opening angle %
13 Check whether oxygen sensor is installed. —
15 Oxygen sensor output voltage and short term fuel trim associated with oxygen sensor V and %
1C Available OBD system—
24 A/F value and A/F sensor output voltage — and V
34 A/F value and A/F sensor current — and mA
PID Data Unit of measure
02 DTC that caused CARB required freeze frame data storage —
03 Fuel system control status—
04 Calculated engine load value%
05 Engine coolant temperature°C
06 Short term fuel trim%
07 Long term whole fuel trim%
0B Intake manifold absolute pressure mmHg
0C Engine speedrpm
0D Vehicle speedkm/h
0E Ignition timing advance°
0F Intake air temperature°C
10 Air flow rate of mass air flow sensor g/sec
11 Throttle valve absolute opening angle %

EN(H4DOTC 2.5)-28
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» screen, select the {Current Data Display/Save}, and then press the [YES] key.
5) On the «Data Display Menu» screen, select the {Data Display} and press the [YES] key.
6) Using the scroll key, move the display screen up or down until the desired data is shown.
 A list of the support data is shown in the following table.
Remarks Display Unit of measure
Battery voltage Battery Voltage V
Vehicle speed signal Vehicle Speed km/h or MPH
Engine speed signal Engine Speed rpm
Engine coolant temperature signal Coolant Temp.°C or °F
Ignition timing signal Ignition Timing deg
Throttle position signal Throttle Opening Angle %
Injection pulse width Fuel Injection #1 Pulse ms
Fuel pump duty control signal Fuel Pump Duty %
A/F sensor current A/F Sensor #1 Current mA
A/F sensor resistance A/F Sensor #1 ResistanceΩ
Front oxygen (A/F) sensor lambda value A/F Sensor #1 —
Rear oxygen sensor output signalRear O
2 Sensor
V
Short term fuel trim A/F Correction #1 %
Knock sensor compensation Knocking Correction deg
Atmospheric pressure signal Atmosphere Pressure mmHg, kPa, inHg or psi
Intake manifold relative pressure signal Mani. Relative Pressure mmHg, kPa, inHg or psi
Intake manifold absolute pressure signal Mani. Absolute Pressure mmHg, kPa, inHg or psi
A/F correction (short term fuel trim) by rear oxygen sensor A/F Correction #3 %
Long term whole fuel trim A/F Learning #1 %
Canister purge control solenoid valve duty ratio CPC Valve Duty Ratio %
Primary supercharged pressure control signal Primary Control %
Tumble generated valve position sensor signal (RH side) TGV Position Sensor R V
Tumble generated valve position sensor signal (LH side) TGV Position Sensor L V
Acceleration opening angle Accel Opening Angle %
VVT advance angle amount (R) VVT Adv. Amount R deg
VVT advance angle amount (L) VVT Adv. amount L deg
OCV duty R OCV Duty R %
OCV duty L OCV Duty L %
OCV current R OCV current R mA
OCV current L OCV Current L mA
Throttle motor duty Throttle Motor Duty %
Throttle power supply voltage Throttle Motor Voltage V
Sub throttle sensor voltage Sub-Throttle Sensor V
Main throttle sensor voltage Main-Throttle Sensor V
Sub acceleration sensor voltage Sub-Accelerator Sensor V
Main acceleration sensor voltage Main-Accelerator Sensor V
Memory vehicle speed Memorized Cruise Speed km/h
Alternate duty ratio ALT Duty %
Exhaust gas temperature signal Exhaust gas temperature°C
Estimated cumulative driving distance Odd Meter Km
Fuel level signal Fuel Level Voltage V
Intake air temperature signal Intake Air Temp.°C or °F
Mass air flow sensor signal Mass Air Flow g/s