
FU(H4SO)-66
FUEL INJECTION (FUEL SYSTEM)
Fuel System Trouble in General
29.Fuel System Trouble in General
A: INSPECTION
NOTE:
When the vehicle is left unattended for an ex-
tended period of time, water may accumulate in the
fuel tank.
To prevent water condensation.
(1) Top off the fuel tank or drain the fuel com-
pletely.
(2) Drain the water condensation from the fuel
filter.
Refilling the fuel tank.
Refill the fuel tank while there is still some fuel left in
the tank.
Protecting the fuel system against freezing and
water condensation.
(3) Cold areas :
In snow-covered areas, mountainous areas, ski-
ing areas, etc. where ambient temperatures
drop below 0°C (32°F) throughout the winter
season, use an anti-freeze solution in the fuel
tank. Refueling will also complement the effect
of anti-freeze solution each time the fuel leveldrops to about one-half. After the winter season,
drain the water which may have accumulated in
the fuel filter and fuel tank in the manner same
as that described under “Affected areas” below.
(4) Affected areas :
When the water condensation is notched in the
fuel filter, drain the water from both the fuel filter
and fuel tank or use a water removing agent (or
anti-freeze solution) in the fuel tank.
Observe the instructions, notes, etc., indicated
on the label affixed to the anti-freeze solution (wa-
ter removing agent) container before use.
Trouble and possible cause Corrective action
1. Insufficient fuel supply to the injector
1) Fuel pump will not operate.
❍Defective terminal contact.Inspect connections, especially ground, and tighten
securely.
❍Trouble in electromagnetic or electronic circuit parts. Replace fuel pump.
2) Lowering of fuel pump function. Replace fuel pump.
3) Clogged dust or water in the fuel filter. Replace fuel filter, clean or replace fuel tank.
4) Clogged or bent fuel pipe or hose. Clean, correct or replace fuel pipe or hose.
5) Air is mixed in the fuel system. Inspect or retighten each connection part.
6) Clogged or bent breather tube or pipe. Clean, correct or replace air breather tube or pipe.
7) Damaged diaphragm of pressure regulator. Replace.
2. Leakage or blow out fuel
1) Loosened joints of the fuel pipe. Retightening.
2) Cracked fuel pipe, hose and fuel tank. Replace.
3) Defective welding part on the fuel tank. Replace.
4) Defective drain packing of the fuel tank. Replace.
5) Clogged or bent air breather tube or air vent tube.Clean, correct or replace air breather tube or air vent
tube.
3. Gasoline smell inside of compartment
1)Loose joints at air breather tube, air vent tube and fuel filler
pipe.Retightening.
2) Defective packing air tightness on the fuel saucer. Correct or replace packing.
3) Cracked fuel separator. Replace separator.
4) Inoperative fuel pump modulator or circuit. Replace.
4. Defective fuel meter indicator
1) Defective operation of fuel level sensor. Replace.
2) Defective operation of fuel meter. Replace.
5. Noise
1) Large operation noise or vibration of fuel pump. Replace.

LU(H4SO)-22
LUBRICATION
Engine Oil Cooler
B: INSTALLATION
NOTE:
Engine oil cooler is equipped with turbo model only.
1) Install in the reverse order of removal.
2) Contact the knock pin (A) of adapter (1) to cylin-
der block rib (B) to install adapter (1).
3) Install the adapter (2).
4) Contact the engine oil cooler stopper (A) to
adapter (2) rib (B) to install engine oil cooler.
Tightening torque:
T1: 6.4 N
⋅m (0.7 kgf-m, 5.1 ft-lb)
T2: 44 N
⋅m (4.5 kgf-m, 33 ft-lb)
T3: 54 N
⋅m (5.5 kgf-m, 40 ft-lb)NOTE:
Always use a new O-ring.
C: INSPECTION
1) Check that the coolant passages are not
clogged using air blow method.
2) Check the mating surfaces of cylinder block, O-
ring groove and oil filter for damage.
LU-00042
(A)
(B)
LU-00043
(B)(A)
(A) Adapter (1)
(B) Adapter connector
(C) Adapter (2)
(D) Oil cooler
(E) Oil cooler connector
LU-00044
(A)
(B)
(C)
(D)
(E)
T1
T2
T3

LU(H4SO)-24
LUBRICATION
Engine Lubrication System Trouble in General
9. Engine Lubrication System Trouble in General
A: INSPECTION
Before performing diagnostics, make sure that the engine oil level is correct and no oil leakage exists.
Trouble Possible cause Corrective action
1. Warning light remains
on.1) Oil pressure switch
failureCracked diaphragm or oil leakage within switch Replace.
Broken spring or seized contacts Replace.
2) Low oil pressureClogged oil filter Replace.
Malfunction of oil by-pass valve of oil filter Clean or replace.
Malfunction of oil relief valve of oil pump Clean or replace.
Clogged oil passage Clean.
Excessive tip clearance and side clearance of oil
pump rotor and gearReplace.
Clogged oil strainer or broken pipe Clean or replace.
3) No oil pressureInsufficient engine oil Replenish.
Broken pipe of oil strainer Replace.
Stuck oil pump rotor Replace.
2. Warning light does
not go on.1) Malfunction of combination meter Replace.
2) Poor contact of switch contact points Replace.
3) Disconnection of wiring Repair.
3. Warning light flickers
momentarily.1) Poor contact at terminals Repair.
2) Defective wiring harness Repair.
3) Low oil pressureCheck for the same
possible causes as
listed in 1. — 2).

EN(H4SO)-256
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 the accelerator cable.
2. AUTOMATIC TRANSMISSION
NOTE:
Check general diagnostics table with non-conformity symptom for automatic transmission.
6. Surging1) Intake manifold pressure sensor
2) Intake air temperature sensor
3) Manifold absolute pressure sensor
4) Engine coolant temperature sensor (*2)
5) Crankshaft position sensor (*3)
6) Camshaft position sensor (*3)
7) Fuel injection parts (*4)
8) Throttle position sensor
9) Fuel pump and fuel pump relay
7. Spark knock1) Intake manifold pressure sensor
2) Intake air temperature sensor
3) Manifold absolute pressure sensor
4) Engine coolant temperature sensor
5) Knock sensor
6) Fuel injection parts (*4)
7) Fuel pump and fuel pump relay
8. After burning in exhaust system1) Intake manifold pressure sensor
2) Intake air temperature sensor
3) Manifold absolute pressure sensor
4) Engine coolant temperature sensor (*2)
5) Fuel injection parts (*4)
6) Fuel pump and fuel pump relay Symptom Problem parts

FUEL INJECTION (FUEL SYSTEM)
FU(H4DOTC)
Page
1. General Description ....................................................................................2
2. Throttle Body .............................................................................................13
3. Intake Manifold ..........................................................................................14
4. Engine Coolant Temperature Sensor........................................................29
5. Crankshaft Position Sensor.......................................................................30
6. Camshaft Position Sensor.........................................................................31
7. AVCS Camshaft Position Sensor ..............................................................32
8. Knock Sensor ............................................................................................33
9. Throttle Position Sensor ............................................................................34
10. Mass Air Flow and Intake Air Temperature Sensor ..................................35
11. Manifold Absolute Pressure Sensor ..........................................................36
12. Idle Air Control Solenoid Valve .................................................................37
13. Fuel Injector ..............................................................................................38
14. Tumble Generator Valve Assembly ..........................................................42
15. Tumble Generator Valve Actuator.............................................................43
16. Wastegate Control Solenoid Valve Assembly ...........................................44
17. Front Oxygen (A/F) Sensor .......................................................................45
18. Rear Oxygen Sensor.................................................................................47
19. Exhaust Temperature Sensor ...................................................................49
20. Engine Control Module (ECM) ..................................................................50
21. Main Relay ................................................................................................51
22. Fuel Pump Relay.......................................................................................52
23. Fuel Pump Control Unit .............................................................................53
24. Fuel ...........................................................................................................54
25. Fuel Tank ..................................................................................................55
26. Fuel Filler Pipe ..........................................................................................58
27. Fuel Pump .................................................................................................62
28. Fuel Level Sensor .....................................................................................64
29. Fuel Sub Level Sensor ..............................................................................65
30. Fuel Filter ..................................................................................................67
31. Fuel Cut Valve...........................................................................................68
32. Fuel Damper Valve ...................................................................................69
33. Fuel Delivery, Return and Evaporation Lines............................................70
34. Fuel System Trouble in General ...............................................................73

FU(H4DOTC)-73
FUEL INJECTION (FUEL SYSTEM)
Fuel System Trouble in General
34.Fuel System Trouble in General
A: INSPECTION
NOTE:
When the vehicle is left unattended for an ex-
tended period of time, water may accumulate in the
fuel tank.
To prevent water condensation.
(1) Top off the fuel tank or drain the fuel com-
pletely.
(2) Drain the water condensation from the fuel
filter.
Refilling the fuel tank.
Refill the fuel tank while there is still some fuel left in
the tank.
Protecting the fuel system against freezing and
water condensation.
Cold areas
In snow-covered areas, mountainous areas, skiing
areas, etc. where ambient temperatures drop be-
low 0°C (32°F) throughout the winter season, use
an anti-freeze solution in the fuel tank. Refueling
will also complement the effect of anti-freeze solu-
tion each time the fuel level drops to about one-half. After the winter season, drain the water which
may have accumulated in the fuel filter and fuel
tank in the manner same as that described under
Affected areas below.
Affected areas
When the water condensation is notched in the fuel
filter, drain the water from both the fuel filter and
fuel tank or use a water removing agent (or anti-
freeze solution) in the fuel tank.
Observe the instructions, notes, etc., indicated
on the label affixed to the anti-freeze solution (wa-
ter removing agent) container before use.
Trouble and possible cause Corrective action
1. Insufficient fuel supply to the injector
1) Fuel pump will not operate.
❍Defective terminal contact.Inspect connections, especially ground, and tighten
securely.
❍Trouble in electromagnetic or electronic circuit parts. Replace fuel pump.
2) Lowering of fuel pump function. Replace fuel pump.
3) Clogged dust or water in the fuel filter. Replace fuel filter, clean or replace fuel tank.
4) Clogged or bent fuel pipe or hose. Clean, correct or replace fuel pipe or hose.
5) Air is mixed in the fuel system. Inspect or retighten each connection part.
6) Clogged or bent breather tube or pipe. Clean, correct or replace air breather tube or pipe.
7) Damaged diaphragm of pressure regulator. Replace.
2. Leakage or blow out fuel
1) Loosened joints of the fuel pipe. Retightening.
2) Cracked fuel pipe, hose and fuel tank. Replace.
3) Defective welding part on the fuel tank. Replace.
4) Defective drain packing of the fuel tank. Replace.
5) Clogged or bent air breather tube or air vent tube.Clean, correct or replace air breather tube or air vent
tube.
3. Gasoline smell inside of compartment
1)Loose joints at air breather tube, air vent tube and fuel filler
pipe.Retightening.
2) Defective packing air tightness on the fuel saucer. Correct or replace packing.
3) Cracked fuel separator. Replace separator.
4) Inoperative fuel pump modulator or circuit. Replace.
4. Defective fuel meter indicator
1) Defective operation of fuel level sensor. Replace.
2) Defective operation of fuel meter. Replace.
5. Noise
1) Large operation noise or vibration of fuel pump. Replace.

EN(H4DOTC)-80
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
19.Diagnostic Procedure with Diagnostic Trouble Code (DTC)
A: DTC P0011 “A” CAMSHAFT POSITION - TIMING OVER - ADVANCED OR
SYSTEM PERFORMANCE (BANK 1)
DTC DETECTING CONDITION:
Detect as soon as the malfunction occurs.
TROUBLE SYMPTOM:
Engine stalls.
Erroneous idling
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode
Step Check Yes No
1 CHECK DTC ON DISPLAY.Is any other DTC displayed? Inspect the rele-
vant DTC using
“List of Diagnostic
Trouble Code
(DTC)”.
List of Diagnostic
Trouble Code
(DTC).>Go to step 2.
2 CHECK CURRENT DATA.
1) Start the engine and idle it.
2) Check the AVCS system operating angle
and oil flow control solenoid valve duty output
using Subaru Select Monitor or OBD-II general
scan tool.
N
OTE:
Subaru Select Monitor
For detailed operation procedure, refer to
“READ CURRENT DATA SHOWN ON DIS-
PLAY FOR ENGINE”.
OBD-II general scan tool
For detailed operation procedures, refer to the
OBD-II General Scan Tool Operation Manual.Is the AVCS system operating
angle approx. 0 degree and oil
flow control solenoid valve duty
output approx. 10%?A temporary poor
malfunction. Per-
for m the following
to clean oil routing.
Replace the
engine oil, and
then idle the
engine for 5 min-
utes and replace
the oil filter and
engine oil.Check the follow-
ing and repair or
replace it if neces-
sary.
Oil pipe (clog-
ging)
Oil flow con-
trol solenoid
valve (clogging
or dirt of oil
routing, spring
setting, clog-
ging of valve)
Intake cam-
shaft (dirt, dam-
age of
camshaft)
Timing belt
(alignment of
timing mark)

EN(H4DOTC)-81
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
B: DTC P0021 “A” CAMSHAFT POSITION - TIMING OVER - ADVANCED OR
SYSTEM PERFORMANCE (BANK 2)
DTC DETECTING CONDITION:
Detect as soon as the malfunction occurs.
TROUBLE SYMPTOM:
Engine stalls.
Erroneous idling
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode
Step Check Yes No
1 CHECK DTC ON DISPLAY.Is any other DTC displayed? Inspect the rele-
vant DTC using
“List of Diagnostic
Trouble Code
(DTC)”.
List of Diagnostic
Trouble Code
(DTC).>Go to step 2.
2 CHECK CURRENT DATA.
1) Start the engine and idle it.
2) Check the AVCS system operating angle
and oil flow control solenoid valve duty output
using Subaru Select Monitor or OBD-II general
scan tool.
NOTE:
Subaru Select Monitor
For detailed operation procedure, refer to
“READ CURRENT DATA SHOWN ON DIS-
PLAY FOR ENGINE”.
OBD-II general scan tool
For detailed operation procedures, refer to the
OBD-II General Scan Tool Operation Manual.Is the AVCS system operating
angle approx. 0 degree and oil
flow control solenoid valve duty
output approx. 10%?A temporary poor
malfunction. Per-
for m the following
to clean oil routing.
Replace the
engine oil, and
then idle the
engine for 5 min-
utes and replace
the oil filter and
engine oil.Check the follow-
ing and repair or
replace it if neces-
sary.
Engine oil
(amount, dirt)
Oil pipe (clog-
ging)
Oil flow con-
trol solenoid
valve (clogging
or dirt of oil
routing, spring
setting, clog-
ging of valve)
Intake cam-
shaft (dirt, dam-
age of
camshaft)
Timing belt
(alignment of
timing mark)