SUBARU FORESTER 2004 Service Repair Manual

EN(H4DOTC)-288
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and oil
flow control solenoid valve.
3) Measure the resistance between ECM and
oil flow control solenoid valve.
Connector & terminal
(B134) No. 18 — (E38) No. 1:
(B134) No. 28 — (E38) No. 2:Is the resistance less than 1
Ω?Go to step 2.Repair open circuit
in harness
between ECM and
oil flow control
solenoid valve
connector.
N
OTE:
In this case, repair
the following:
 Open circuit in
harness between
ECM and oil flow
control solenoid
valve connector
 Poor contact in
coupling connector
2 CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
Measure the resistance between ECM and oil
flow control solenoid valve.
Connector & terminal
(E38) No. 1 — Engine ground:
(E38) No. 2 — Engine ground:Is the resistance more than 1
MΩ?Go to step 3.Repair short circuit
between ECM and
oil flow control
solenoid valve
connector.
3 CHECK OIL FLOW CONTROL SOLENOID
VALVE.
1) Remove the oil flow control solenoid valve
connector.
2) Measure the resistance between oil flow
control solenoid valve terminals.
Te r m i n a l s
No. 1 — No. 2:Is the resistance 6 — 12 Ω? Repair poor con-
tact in ECM and oil
flow control sole-
noid valve.Replace the oil
flow control sole-
noid valve. to ME(H4DOTC)-
68, Camshaft.>

EN(H4DOTC)-289
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
CV:DTC P2089 OCV SOLENOID VALVE SIGNAL A CIRCUIT SHORT (BANK 1)
DTC DETECTING CONDITION:
Two consecutive driving cycles with fault
TROUBLE SYMPTOM:
Erroneous idling
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode ERATION, Clear Memory Mode.> and Inspection Mode spection Mode.>.
WIRING DIAGRAM:
EN-02349
F61
: LHD
E2
B134
B134
E38
OIL FLOW CONTROL
SOLENOID VALVE RHECM
28 2 1
2
1
B62
F45
RHD
RHD
LHD LHD
RHD
RHD
LHD LHD
: LHD
: RHD
B22
E38
F61
12
F45
B22
: RHD
18
125678
131415169101112
34
17181920
56 7
82 1
94 310
24 22 23 25 11 12 13 14 15
26 27
2816 17
18 19 20 21
33 34 29
32 30 31
12345678910111213141516
: LHDE3
: RHD
1
7

EN(H4DOTC)-290
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and oil
flow control solenoid valve.
3) Measure the resistance between ECM and
oil flow control solenoid valve.
Connector & terminal
(B134) No. 18 — (E38) No. 1:
(B134) No. 28 — (E38) No. 2:Is the resistance less than 1
Ω?Go to step 2.Repair open circuit
in harness
between ECM and
oil flow control
solenoid valve
connector.
N
OTE:
In this case, repair
the following:
 Open circuit in
harness between
ECM and oil flow
control solenoid
valve connector
 Poor contact in
coupling connector
2 CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and oil
flow control solenoid valve.
3) Measure the resistance between ECM and
oil flow control solenoid valve.
Connector & terminal
(E38) No. 1 — Engine ground:
(E38) No. 2 — Engine ground:Is the resistance more than 1
MΩ?Go to step 3.Repair short circuit
between ECM and
oil flow control
solenoid valve
connector.
3 CHECK OIL FLOW CONTROL SOLENOID
VALVE.
1) Remove the oil flow control solenoid valve
connector.
2) Measure the resistance between oil flow
control solenoid valve terminals.
Te r m i n a l s
No. 1 — No. 2:Is the resistance 6 — 12 Ω? Repair poor con-
tact in ECM and oil
flow control sole-
noid valve.Replace the oil
flow control sole-
noid valve. to ME(H4DOTC)-
68, Camshaft.>

EN(H4DOTC)-291
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
CW:DTC P2092 OCV SOLENOID VALVE SIGNAL A CIRCUIT OPEN (BANK 2)
DTC DETECTING CONDITION:
Two consecutive driving cycles with fault
TROUBLE SYMPTOM:
Erroneous idling
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode ERATION, Clear Memory Mode.> and Inspection Mode spection Mode.>.
WIRING DIAGRAM:
EN-02350
F61
: LHD
E2
B134B134
E37 ECM
29 2 1
4
3
B62
F45
RHD
RHD
LHD LHD
RHD
RHD
LHD LHD
: LHD
: RHD
B22
E37
F61
12
F45
B22
: RHD
19
125678
131415169101112
34
17181920
OIL FLOW CONTROL
SOLENOID VALVE LH
56 7
82 1
94 310
24 22 23 25 11 12 13 14 15
26 27
2816 17
18 19 20 21
33 34 29
32 30 31
12345678910111213141516
F44
12345678
B61
F44
: LHD
E3
: RHD
8
6

EN(H4DOTC)-292
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and oil
flow control solenoid valve.
3) Measure the resistance between ECM and
oil flow control solenoid valve.
Connector & terminal
(B134) No. 19 — (E37) No. 1:
(B134) No. 29 — (E37) No. 2:Is the resistance less than 1
Ω?Go to step 2.Repair open circuit
in harness
between ECM and
oil flow control
solenoid valve
connector.
N
OTE:
In this case, repair
the following:
 Open circuit in
harness between
ECM and oil flow
control solenoid
valve connector
 Poor contact in
coupling connector
2 CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
Measure the resistance between ECM and oil
flow control solenoid valve.
Connector & terminal
(E37) No. 1 — Engine ground:
(E37) No. 2 — Engine ground:Is the resistance more than 1
MΩ?Go to step 3.Repair short circuit
between ECM and
oil flow control
solenoid valve
connector.
3 CHECK OIL FLOW CONTROL SOLENOID
VALVE.
1) Remove the oil flow control solenoid valve
connector.
2) Measure the resistance between oil flow
control solenoid valve terminals.
Te r m i n a l s
No. 1 — No. 2:Is the resistance 6 — 12 Ω? Repair poor con-
tact in ECM and oil
flow control sole-
noid valve.Replace the oil
flow control sole-
noid valve. to ME(H4DOTC)-
68, Camshaft.>

EN(H4DOTC)-293
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
CX:DTC P2093 OCV SOLENOID VALVE SIGNAL A CIRCUIT SHORT (BANK 2)
DTC DETECTING CONDITION:
Two consecutive driving cycles with fault
TROUBLE SYMPTOM:
Erroneous idling
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode ERATION, Clear Memory Mode.> and Inspection Mode spection Mode.>.
WIRING DIAGRAM:
EN-02350
F61
: LHD
E2
B134B134
E37 ECM
29 2 1
4
3
B62
F45
RHD
RHD
LHD LHD
RHD
RHD
LHD LHD
: LHD
: RHD
B22
E37
F61
12
F45
B22
: RHD
19
125678
131415169101112
34
17181920
OIL FLOW CONTROL
SOLENOID VALVE LH
56 7
82 1
94 310
24 22 23 25 11 12 13 14 15
26 27
2816 17
18 19 20 21
33 34 29
32 30 31
12345678910111213141516
F44
12345678
B61
F44
: LHD
E3
: RHD
8
6

EN(H4DOTC)-294
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and oil
flow control solenoid valve.
3) Measure the resistance between ECM and
oil flow control solenoid valve.
Connector & terminal
(B134) No. 19 — (E37) No. 1:
(B134) No. 29 — (E37) No. 2:Is the resistance less than 1
Ω?Go to step 2.Repair open circuit
in harness
between ECM and
oil flow control
solenoid valve
connector.
N
OTE:
In this case, repair
the following:
 Open circuit in
harness between
ECM and oil flow
control solenoid
valve connector
 Poor contact in
coupling connector
2 CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and oil
flow control solenoid valve.
3) Measure the resistance between ECM and
oil flow control solenoid valve.
Connector & terminal
(E37) No. 1 — Engine ground:
(E37) No. 2 — Engine ground:Is the resistance more than 1
MΩ?Go to step 3.Repair short circuit
between ECM and
oil flow control
solenoid valve
connector.
3 CHECK OIL FLOW CONTROL SOLENOID
VALVE.
1) Remove the oil flow control solenoid valve
connector.
2) Measure the resistance between oil flow
control solenoid valve terminals.
Te r m i n a l s
No. 1 — No. 2:Is the resistance 6 — 12 Ω? Repair poor con-
tact in ECM and oil
flow control sole-
noid valve.Replace the oil
flow control sole-
noid valve. to ME(H4DOTC)-
68, Camshaft.>

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. 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)