engine SUBARU FORESTER 2004 Service Repair Manual

EN(H4DOTC)-295
ENGINE (DIAGNOSTIC)
General Diagnostic Table
20.General Diagnostic Table
A: INSPECTION
1. ENGINE
NOTE:
Malfunction of parts other than those listed is also possible. <Ref. to ME(H4DOTC)-118, Engine Trouble in
General.>
Symptom Problem parts
1. Engine stalls during idling.1) Idle air control solenoid valve
2) Manifold absolute pressure sensor
3) Mass air flow and intake air temperature sensor
4) Ignition parts (*1)
5) Engine coolant temperature sensor (*2)
6) Crankshaft position sensor (*3)
7) Camshaft position sensor (*3)
8) Fuel injection parts (*4)
2. Rough idling1) Idle air control solenoid valve
2) Manifold absolute pressure sensor
3) Mass air flow and intake air temperature sensor
4) Engine coolant temperature sensor (*2)
5) Ignition parts (*1)
6) Air intake system (*5)
7) Fuel injection parts (*4)
8) Throttle position sensor
9) Crankshaft position sensor (*3)
10) Camshaft position sensor (*3)
11) Oxygen sensor
12) Fuel pump and fuel pump relay
3. Engine does not return to idle.1) Idle air control solenoid valve
2) Engine coolant temperature sensor
3) Accelerator cable (*6)
4) Throttle position sensor
5) Manifold absolute pressure sensor
6) Mass air flow sensor
4. Poor acceleration1) Manifold absolute pressure sensor
2) Mass air flow and intake air temperature sensor
3) Throttle position sensor
4) Fuel injection parts (*4)
5) Fuel pump and fuel pump relay
6) Engine coolant temperature sensor (*2)
7) Crankshaft position sensor (*3)
8) Camshaft position sensor (*3)
9) A/C switch and A/C cut relay
10) Engine torque control signal circuit
11) Ignition parts (*1)
5. Engine stalls or engine sags or hesitates at
acceleration.1) Manifold absolute pressure sensor
2) Mass air flow and intake air temperature sensor
3) Engine coolant temperature sensor (*2)
4) Crankshaft position sensor (*3)
5) Camshaft position sensor (*3)
6) Purge control solenoid valve
7) Fuel injection parts (*4)
8) Throttle position sensor
9) Fuel pump and fuel pump relay

EN(H4DOTC)-296
ENGINE (DIAGNOSTIC)
General Diagnostic Table
*1: Check ignition coil & ignitor ASSY and spark plug.
*2: Indicate the symptom occurring only in cold temperatures.
*3: Ensure the secure installation.
*4: Check fuel injector, fuel pressure regulator and fuel filter.
*5: Inspect air leak in air intake system.
*6: Adjust accelerator cable. 6. Surging1) Manifold absolute pressure sensor
2) Mass air flow and intake air temperature sensor
3) Engine coolant temperature sensor (*2)
4) Crankshaft position sensor (*3)
5) Camshaft position sensor (*3)
6) Fuel injection parts (*4)
7) Throttle position sensor
8) Fuel pump and fuel pump relay
7. Spark knock1) Manifold absolute pressure sensor
2) Mass air flow and intake air temperature sensor
3) Engine coolant temperature sensor
4) Knock sensor
5) Fuel injection parts (*4)
6) Fuel pump and fuel pump relay
8. After burning in exhaust system1) Manifold absolute pressure sensor
2) Mass air flow and intake air temperature sensor
3) Engine coolant temperature sensor (*2)
4) Fuel injection parts (*4)
5) Fuel pump and fuel pump relay Symptom Problem parts

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)

FUEL INJECTION (FUEL SYSTEM)
FU(H4DOTC 2.5)
Page
1. General Description ....................................................................................2
2. Throttle Body .............................................................................................13
3. Intake Manifold ..........................................................................................14
4. Engine Coolant Temperature Sensor........................................................26
5. Crankshaft Position Sensor.......................................................................27
6. Camshaft Position Sensor.........................................................................28
7. Knock Sensor ............................................................................................29
8. Mass Air Flow and Intake Air Temperature Sensor ..................................30
9. Manifold Absolute Pressure Sensor ..........................................................31
10. Fuel Injector ..............................................................................................32
11. Tumble Generator Valve Assembly ..........................................................33
12. Tumble Generator Valve Actuator.............................................................34
13. Wastegate Control Solenoid Valve ...........................................................35
14. Front Oxygen (A/F) Sensor .......................................................................36
15. Rear Oxygen Sensor.................................................................................38
16. Exhaust Temperature Sensor ...................................................................40
17. Engine Control Module (ECM) ..................................................................41
18. Main Relay ................................................................................................42
19. Fuel Pump Relay.......................................................................................43
20. Fuel Pump Control Unit .............................................................................44
21. Fuel ...........................................................................................................45
22. Fuel Tank ..................................................................................................46
23. Fuel Filler Pipe ..........................................................................................48
24. Fuel Pump .................................................................................................52
25. Fuel Level Sensor .....................................................................................54
26. Fuel Sub Level Sensor ..............................................................................55
27. Fuel Filter ..................................................................................................57
28. Fuel Cut Valve...........................................................................................58
29. Fuel Damper Valve ...................................................................................59
30. Fuel Delivery, Return and Evaporation Lines............................................60
31. Fuel System Trouble in General ...............................................................63

FU(H4DOTC 2.5)-13
FUEL INJECTION (FUEL SYSTEM)
Throttle Body
2. Throttle Body
A: REMOVAL
1) Disconnect the ground cable from battery.
2) Remove the intercooler. <Ref. to IN(H4DOTC)-
10, REMOVAL, Intercooler.>
3) Disconnect the connector from the throttle posi-
tion sensor (A) and manifold absolute pressure sen-
sor (B).
4) Disconnect the engine coolant hoses from the
throttle body.
5) Remove the bolts which secure the throttle body
to intake manifold.
B: INSTALLATION
Install in the reverse order of removal.
NOTE:
Always use a new gasket.
Tightening torque:
8 N·m (0.8 kgf-m, 5.8 ft-lb)
FU-00009
FU-01073
(A)
(B)
FU-01074
FU-01075

FU(H4DOTC 2.5)-14
FUEL INJECTION (FUEL SYSTEM)
Intake Manifold
3. Intake Manifold
A: REMOVAL
1) Release the fuel pressure.
<Ref. to FU(H4DOTC 2.5)-45, RELEASING OF
FUEL PRESSURE, OPERATION, Fuel.>
2) Open the fuel filler flap lid and remove the fuel
filler cap.
3) Disconnect the ground cable from battery.
4) Lift up the vehicle.
5) Remove the under cover.
6) Drain the engine coolant about 3.02 (3.2 US qt,
2.6 Imp qt).
7) Remove the air cleaner upper cover and air in-
take boot. <Ref. to IN(H4DOTC)-7, REMOVAL, Air
Cleaner.>
8) Remove the air cleaner element.
9) Remove the intercooler. <Ref. to IN(H4DOTC)-
10, REMOVAL, Intercooler.>
10) Remove the coolant filler tank. <Ref. to
CO(H4SO)-42, REMOVAL, Coolant Filler Tank.>
11) Remove the power steering pump.
(1) Remove the front side V-belt. <Ref. to
ME(H4DOTC)-52, REMOVAL, V-belt.>(2) Disconnect the power steering switch con-
nector.
(3) Remove the bolts which secure the power
steering pipe brackets to the intake manifold.
NOTE:
Do not disconnect the power steering hose.
(4) Remove the bolts which secure the power
steering pump bracket.
(5) Remove the reservoir tank from the bracket
by pulling it upward.
FU-00009
FU-00016
FU-00017
FU-00018
FU-00019
FU-00020

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)-16
FUEL INJECTION (FUEL SYSTEM)
Intake Manifold
18) Disconnect the knock sensor connector.
19) Disconnect the connector from the camshaft
position sensor.
20) Disconnect the connector from the ignition coil.
 RH SIDE
 LH SIDE
21) Disconnect the engine harness fixed by clip (A)
from the bracket. RH SIDE
 LH SIDE
22) Disconnect the fuel delivery hose, return hose
and evaporation hose.
CAUTION:
 Do not spill fuel.
 Catch fuel from hoses in a container or cloth.
23) Remove the bolts which secure the intake man-
ifold to the cylinder heads.
24) Remove the intake manifold.
FU-00028
FU-01038
FU-01307
FU-01308
FU-01309 (A)
FU-01310
(A)
FU-00032
FU-01039

FU(H4DOTC 2.5)-17
FUEL INJECTION (FUEL SYSTEM)
Intake Manifold
B: INSTALLATION
1) Install the intake manifold onto cylinder heads.
NOTE:
Always use new gaskets.
Tightening torque:
25 N·m (2.5 kgf-m, 18.1 ft-lb)
2) Connect the fuel delivery hose, return hose and
evaporation hose.
3) Connect the connector to the oil pressure switch
(B), crankshaft position sensor (C) and engine cool-
ant temperature sensor (A).4) Connect the connector to the knock sensor.
5) Connect the connector to the camshaft position
sensor.
6) Connect the connector to the ignition coil.
7) Connect the engine harness with clip (A) to the
bracket.
 RH SIDE
FU-01039
FU-00032
(A)
(B)
(C)
FU-00027
FU-00028
FU-01038
FU-00030
FU-01309 (A)

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