2004 SUBARU FORESTER fuel

ME(H4SO)-92
MECHANICAL
Engine Trouble in General
4) Engine stalls after initial
combustion. Engine control system A
Intake system Loosened or cracked intake duct B
Loosened or cracked PCV hose C
Loosened or cracked vacuum hose C
Defective intake manifold gasket B
Defective throttle body gasket B
Dirty air cleaner element C
Fuel line Clogged fuel line C
Lack of or insufficient fuel B
Belt Defective B
Defective timing B
Compression Incorrect valve clearance C
Loosened spark plugs or defective gasket C
Loosened cylinder head bolts or defective gasket C
Improper valve seating C
Defective valve stem C
Worn or broken valve spring B
Worn or stuck piston rings, cylinder and piston C
Incorrect valve timing B
Improper engine oil (low viscosity) B
2. Rough idle and engine
stallEngine control system A
Intake system Loosened or cracked intake duct A
Loosened or cracked PCV hose A
Loosened or cracked vacuum hose A
Defective intake manifold gasket B
Defective throttle body gasket B
Defective PCV valve C
Loosened oil filler cap B
Dirty air cleaner element C
Fuel line Defective fuel pump and relay C
Clogged fuel line C
Lack of or insufficient fuel B
Belt Defective timing C
Compression Incorrect valve clearance B
Loosened spark plugs or defective gasket B
Loosened cylinder head bolts or defective gasket B
Improper valve seating B
Defective valve stem C
Worn or broken valve spring B
Worn or stuck piston rings, cylinder and piston B
Incorrect valve timing A
Improper engine oil (low viscosity) B
Lubrication system Incorrect oil pressure B
Defective rocker cover gasket C
Cooling system Overheating C
Others Malfunction of evaporative emission control system A
Stuck or damaged throttle valve B
Accelerator cable out of adjustment C TROUBLE PROBLEM PARTS, ETC. POSSIBLE CAUSE RANK

ME(H4SO)-93
MECHANICAL
Engine Trouble in General
3. Low output, hesitation and
poor accelerationEngine control system A
Intake system Loosened or cracked intake duct A
Loosened or cracked PCV hose A
Loosened or cracked vacuum hose B
Defective intake manifold gasket B
Defective throttle body gasket B
Defective PCV valve B
Loosened oil filler cap B
Dirty air cleaner element A
Fuel line Defective fuel pump and relay B
Clogged fuel line B
Lack of or insufficient fuel C
Belt Defective timing B
Compression Incorrect valve clearance B
Loosened spark plugs or defective gasket B
Loosened cylinder head bolts or defective gasket B
Improper valve seating B
Defective valve stem C
Worn or broken valve spring B
Worn or stuck piston rings, cylinder and piston C
Incorrect valve timing A
Improper engine oil (low viscosity) B
Lubrication system Incorrect oil pressure B
Cooling system Overheating C
Over cooling C
Others Malfunction of evaporative emission control system A
4. Surging Engine control system A
Intake system Loosened or cracked intake duct A
Loosened or cracked PCV hose A
Loosened or cracked vacuum hose A
Defective intake manifold gasket B
Defective throttle body gasket B
Defective PCV valve B
Loosened oil filler cap B
Dirty air cleaner element B
Fuel line Defective fuel pump and relay B
Clogged fuel line B
Lack of or insufficient fuel C
Belt Defective timing B
Compression Incorrect valve clearance B
Loosened spark plugs or defective gasket C
Loosened cylinder head bolts or defective gasket C
Improper valve seating C
Defective valve stem C
Worn or broken valve spring C
Worn or stuck piston rings, cylinder and piston C
Incorrect valve timing A
Improper engine oil (low viscosity) B
Cooling system Overheating B
Others Malfunction of evaporative emission control system C TROUBLE PROBLEM PARTS, ETC. POSSIBLE CAUSE RANK

ME(H4SO)-95
MECHANICAL
Engine Trouble in General
10. Excessive fuel consump-
tionEngine control system A
Intake system Dirty air cleaner element A
Belt Defective timing B
Compression Incorrect valve clearance B
Loosened spark plugs or defective gasket C
Loosened cylinder head bolts or defective gasket C
Improper valve seating B
Defective valve stem C
Worn or broken valve spring C
Worn or stuck piston rings, cylinder and piston B
Incorrect valve timing B
Lubrication system Incorrect oil pressure C
Cooling system Over cooling C
Others Accelerator cable out of adjustment B TROUBLE PROBLEM PARTS, ETC. POSSIBLE CAUSE RANK

ME(H4SO)-96
MECHANICAL
Engine Noise
23.Engine Noise
A: INSPECTION
NOTE*:
When disconnecting fuel injector connector, the malfunction indicator light illuminates and DTC is stored in ECM memory.
Therefore, carry out the clear memory mode and inspection mode
after connecting fuel injector connector.Type of sound Condition Possible cause
Regular clicking soundSound increases as engine
speed increases. Valve mechanism is defective.
 Incorrect valve clearance
 Worn valve rocker
 Worn camshaft
 Broken valve spring
Heavy and dull clankOil pressure is low. Worn crankshaft main bearing
 Worn connecting rod bearing (big end)
Oil pressure is normal. Loose flywheel mounting bolts
 Damaged engine mounting
High-pitched clank (Spark
knock)Sound is noticeable when
accelerating with an overload. Ignition timing advanced
 Accumulation of carbon inside combustion chamber
 Wrong spark plug
 Improper gasoline
Clank when engine speed is
medium (1,000 to 2,000 rpm).Sound is reduced when fuel
injector connector of noisy cyl-
inder is disconnected.
(NOTE*) Worn crankshaft main bearing
 Worn bearing at crankshaft end of connecting rod
Knocking sound when engine
is operating under idling speed
and engine is warmSound is reduced when fuel
injector connector of noisy cyl-
inder is disconnected.
(NOTE*) Worn cylinder liner and piston ring
 Broken or stuck piston ring
 Worn piston pin and hole at piston end of connecting rod
Sound is not reduced if each
fuel injector connector is dis-
connected in turn. (NOTE*) Unusually worn valve lifter
 Worn cam gear
 Worn camshaft journal bore in crankcase
Squeaky sound — Insufficient generator lubrication
Rubbing sound — Defective generator brush and rotor contact
Gear scream when starting
engine— Defective ignition starter switch
 Worn gear and starter pinion
Sound like polishing glass with
a dry cloth— Loose drive belt
 Defective water pump shaft
Hissing sound — Loss of compression
 Air leakage in air intake system, hoses, connections or mani-
folds
Timing belt noise — Loose timing belt
 Belt contacting case/adjacent part
Valve tappet noise — Incorrect valve clearance

FUJI HEAVY INDUSTRIES LTD. G8080GE2
2004 FORESTER SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE SECTION 1
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(H4SO)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICE)EC(H4SO)
INTAKE (INDUCTION) IN(H4SO)
MECHANICAL ME(H4SO)
EXHAUST EX(H4SO)
COOLING CO(H4SO)
LUBRICATION LU(H4SO)
SPEED CONTROL SYSTEM SP(H4SO)
IGNITION IG(H4SO)
STARTING/CHARGING SYSTEM SC(H4SO)
ENGINE (DIAGNOSTIC) EN(H4SO)

FUJI HEAVY INDUSTRIES LTD. G8080GE2
2004 FORESTER SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE SECTION 1
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(H4SO)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICE)EC(H4SO)
INTAKE (INDUCTION) IN(H4SO)
MECHANICAL ME(H4SO)
EXHAUST EX(H4SO)
COOLING CO(H4SO)
LUBRICATION LU(H4SO)
SPEED CONTROL SYSTEM SP(H4SO)
IGNITION IG(H4SO)
STARTING/CHARGING SYSTEM SC(H4SO)
ENGINE (DIAGNOSTIC) EN(H4SO)

CO(H4SO)-43
COOLING
Engine Cooling System Trouble in General
12.Engine Cooling System Trouble in General
A: INSPECTION
Trouble Possible cause Corrective action
Over-heatinga. Insufficient engine coolantReplenish the engine coolant, inspect for leakage, and
repair.
b. Loose timing belt Repair or replace the timing belt tensioner.
c. Oil on drive belt Replace.
d. Malfunction of thermostat Replace.
e. Malfunction of water pump Replace.
f. Clogged engine coolant passage Clean.
g. Improper ignition timingInspect and repair the ignition control system.

nostics Procedure.>
h. Clogged or leaking radiator Clean or repair, or replace.
i. Improper engine oil in engine coolant Replace the engine coolant.
j. Air/fuel mixture ratio too leanInspect and repair the fuel injection system.

nostics Procedure.>
k. Excessive back pressure in exhaust system Clean or replace.
l. Insufficient clearance between piston and cylinder Adjust or replace.
m. Slipping clutch Repair or replace.
n. Dragging brake Adjust.
o. Defective thermostat Replace.
p. Malfunction of radiator fanInspect the radiator fan relay, engine coolant tempera-
ture sensor or radiator motor and replace there.
Over-coolinga. Atmospheric temperature extremely low Partly cover the radiator front area.
b. Defective thermostat Replace.
Engine coolant
leaks.a. Loosened or damaged connecting units on hoses Repair or replace.
b. Leakage from water pump Replace.
c. Leakage from water pipe Repair or replace.
d. Leakage around cylinder head gasket Retighten the cylinder head bolts or replace gasket.
e. Damaged or cracked cylinder head and crankcase Repair or replace.
f. Damaged or cracked thermostat case Repair or replace.
g. Leakage from radiator Repair or replace.
Noisea. Defective drive belt Replace.
b. Defective radiator fan Replace.
c. Defective water pump bearing Replace the water pump.
d. Defective water pump mechanical seal Replace the water pump.

FUJI HEAVY INDUSTRIES LTD. G8080GE2
2004 FORESTER SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE SECTION 1
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(H4SO)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICE)EC(H4SO)
INTAKE (INDUCTION) IN(H4SO)
MECHANICAL ME(H4SO)
EXHAUST EX(H4SO)
COOLING CO(H4SO)
LUBRICATION LU(H4SO)
SPEED CONTROL SYSTEM SP(H4SO)
IGNITION IG(H4SO)
STARTING/CHARGING SYSTEM SC(H4SO)
ENGINE (DIAGNOSTIC) EN(H4SO)