fuel pump SUBARU FORESTER 2004 Service Owner's Manual

ME(H4SO)-91
MECHANICAL
Engine Trouble in General
22.Engine Trouble in General
A: INSPECTION
NOTE:
“RANK” shown in the chart refer to the possibility of reason for the trouble in order (“Very often” to “Rarely”)
A — Very often
B — Sometimes
C — Rarely
TROUBLE PROBLEM PARTS, ETC. POSSIBLE CAUSE RANK
1. Engine will not start.
1) Starter does not turn. Starter Defective battery-to-starter harness B
Defective starter switch C
Defective inhibitor switch or neutral switch C
Defective starter B
Battery Poor terminal connection A
Run-down battery A
Defective charging system B
Friction Seizure of crankshaft and connecting rod bearing C
Seized camshaft C
Seized or stuck piston and cylinder C
2) Initial combustion does
not occur. Starter Defective starter C
Engine control system A
Fuel line Defective fuel pump and relay A
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
3) Initial combustion occurs. Engine control system A
Intake system Defective intake manifold gasket B
Defective throttle body gasket B
Fuel line Defective fuel pump and relay C
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

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)-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

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.

EN(H4SO)-6
ENGINE (DIAGNOSTIC)
General Description
3. General Description
A: CAUTION
1) Airbag system wiring harness is routed near the
ECM, main relay and fuel pump relay.
CAUTION:
 All air bag system wiring harnesses and con-
nectors are yellow. Do not use the electrical
test equipment on these circuits.
 Be careful not to damage the Airbag system
wiring harness when servicing the ECM, TCM,
main relay and fuel pump relay.
2) Never connect the battery in reverse polarity.
 The ECM will be destroyed immediately.
 The fuel injector and other part will be damaged.
3) Do not disconnect the battery terminals while the
engine is running.
A large counter electromotive force will be generat-
ed in the generator, and this voltage may damage
electronic parts such as ECM, etc.
4) Before disconnecting the connectors of each
sensor and the ECM, be sure to turn the ignition
switch to OFF.
5) Poor contact has been identified as a primary
cause of this problem. Measure the voltage or re-
sistance of individual sensor or all electrical control
modules using a tapered pin with a diameter of less
than 0.64 mm (0.025 in). Do not insert the pin more
than 5 mm (0.20 in) into the part.
6) Remove the ECM from the located position after
disconnecting two cables on battery.
Otherwise, the ECM may be damaged.
CAUTION:
When replacing the ECM, be careful not to use
the wrong spec. ECM to avoid any damage on
the fuel injection system.
7) Connectors to each sensor in the engine com-
partment and the harness connectors on the en-
gine side and body side are all designed to be
waterproof. However, it is still necessary to take
care not to allow water to get into the connectors
when washing the vehicle, or when servicing the
vehicle on a rainy day.8) Use ECM mounting stud bolts as the grounding
point to body when measuring voltage and resis-
tance inside the passenger compartment.
9) Use engine ground terminal or engine proper as
the grounding point to body when measuring volt-
age and resistance in the engine compartment.
10) Use TCM mounting stud bolts as the grounding
point to body when measuring voltage and resis-
tance inside the passenger compartment.
11) Every MFI-related part is a precision part. Do
not drop them.
12) Observe the following cautions when installing
a radio in MFI equipped models.
CAUTION:
 The antenna must be kept as far apart as pos-
sible from the control unit. (The ECM is located
under the steering column, inside of the instru-
ment panel lower trim panel.)
(A) Stud bolt
(A) Stud bolt
EN-00001
(A)
EN-00153
EN-00154(A)

EN(H4SO)-7
ENGINE (DIAGNOSTIC)
General Description
 The antenna feeder must be placed as far
apart as possible from the ECM and MFI har-
ness.
 Carefully adjust the antenna for correct
matching.
 When mounting a large power type radio, pay
special attention to the three items above men-
tioned.
 Incorrect installation of the radio may affect
the operation of the ECM.
13) Before disconnecting the fuel hose, disconnect
the fuel pump connector and crank the engine for
more than five seconds to release pressure in the
fuel system. If engine starts during this operation,
run it until it stops.
14) Problems in the electronic-controlled automatic
transmission may be caused by failure of the en-
gine, the electronic control system, the transmis-
sion proper, or by a combination of these. These
three causes must be distinguished clearly when
performing diagnostics.
15) 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.
16) In AT models, do not continue the stall for more
than five seconds. (from closed throttle, fully open
throttle to stall engine speed.)
17) 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 grounding terminal is proper-
ly 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.
EN-00153

EN(H4SO)-16
ENGINE (DIAGNOSTIC)
Electrical Component Location
 LHD MODEL
 RHD MODEL
(1) Inhibitor switch (4) Fuel pump relay (7) Starter
(2) Fuel pump (5) Radiator main fan relay
(3) Main relay (6) Radiator sub fan relay
EN-00251
(3)
(4)
EN-02400
EN-00252 (1)
(3) (7) (6)(5)(4)
(2)
EN-00253
(7) (6)(5)
(2)(3)(4)(1)

EN(H4SO)-22
ENGINE (DIAGNOSTIC)
Engine Control Module (ECM) I/O Signal
A/C switch B136 11ON: 10 — 13
OFF: 0ON: 12 — 14
OFF: 0—
Ignition switch B136 10 10 — 13 12 — 14 —
Neutral
Po si ti o n
SwitchMT B136 21ON: 12±0.5
OFF: 0Switch is ON when gear is in
neutral position.
AT B136 21ON: 0
OFF: 12±0.5Switch is ON when shifted into
“P” or “N” range.
Test Mode Connector B136 3 5 5 When connected: 0
Knock
sensorSignal B135 16 2.8 2.8 —
Shield B135 27 0 0 —
Back-up power supply B135 9 10 — 13 12 — 14 Ignition switch “OFF”: 10 — 13
Control module power
supplyB135 1 10 — 13 12 — 14 —
B135 2 10 — 13 12 — 14 —
Sensor power supply B135 3 5 5 —
Ignition
control#1, #2 B134 33 0 1 — 3.4 Waveform
#3, #4 B134 32 0 1 — 3.4 Waveform
Fuel injec-
tor#1 B134 34 10 — 13 1 — 14 Waveform
#2 B134 23 10 — 13 1 — 14 Waveform
#3 B134 22 10 — 13 1 — 14 Waveform
#4 B134 8 10 — 13 1 — 14 Waveform
Idle air
control
solenoid
valveSignal 1 B134 20 — 1 — 13 Waveform
Signal 2 B134 6 — 1 — 13 Waveform
Signal 3 B134 5 — 1 — 13 Waveform
Signal 4 B134 19 — 1 — 13 Waveform
Pow er
supplyB135 2 10 — 13 12 — 14 —
Fuel pump relay control B134 2ON: 0.5, or less
OFF: 10 — 130.5, or less —
A/C relay control B134 9ON: 0.5, or less
OFF: 10 — 13ON: 0.5, or less
OFF: 12 — 14—
Heater cock solenoid B134 11 10 — 13 12 — 14 —
Radiator fan relay 1 con-
trolB134 14ON: 0.5, or less
OFF: 10 — 13ON: 0.5, or less
OFF: 12 — 14—
Radiator fan relay 2 con-
trolB134 13ON: 0.5, or less
OFF: 10 — 13ON: 0.5, or less
OFF: 12 — 14Model with A/C
Self-shutoff control B136 12 10 — 13 12 — 14 —
Malfunction indicator
lightB134 28 — —Light “ON”: 1, or less
Light “OFF”: 10 — 14
Engine speed output B134 10 — 0 — 13, or more Waveform
Torque control 1 signal B136 1 5 5 —
Torque control 2 signal B136 18 5 5 —
Torque control cut signal B136 15 8 8 —
Purge control solenoid
valveB134 29ON: 1, or less
OFF: 10 — 13ON: 1, or less
OFF: 12 — 14—
Fuel level sensor B135 25 0.12 — 4.75 0.12 — 4.75 —
EGR valveSignal 1 B134 18 0 or 10 — 13 0 or 10 — 13 —
Signal 2 B134 17 0 or 10 — 13 0 or 10 — 13 —
Signal 3 B134 16 0 or 10 — 13 0 or 10 — 13 —
Signal 4 B134 15 0 or 10 — 13 0 or 10 — 13 —
AT diagnosis input sig-
nalB137 19Less than 1←→
More than 4Less than 1←→
More than 4Wavefor m DESCRIPTION Connector No. Terminal No.Signal (V)
NOTE
Ignition SW ON
(engine OFF)Engine ON
(Idling)

EN(H4SO)-30
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» display screen, select the {Current Data Display/Save}, and then press the
[YES] key.
5) On the «Data Display Menu» display screen, select the {Data Display} and press the [YES] key.
6) Using the scroll key, scroll the display screen up or down until the desired data is shown.
 A list of the support data is shown in the following table.
Description Display Unit of measure
Battery voltage Battery Voltage V
Vehicle speed signal Meter vehicle speed km/h or MPH
Engine speed signal Engine speed rpm
Engine coolant temperature signal Engine coolant temperature°C or (°F)
Ignition timing signal Ignition timing deg
Throttle position signal Amount of intake air %
Throttle position signal Throttle Sensor Voltage V
Injection pulse width Fuel injection pulse width ms
Idle air control signal ISC Steps STEP
Engine load data Engine load %
Front oxygen (A/F) sensor resistance A/F sensor resistance value 1 ohm
Front oxygen (A/F) sensor output signal A/F sensor current value 1 —
Rear oxygen sensor output signalRear oxygen sensor voltage
valueV
Short term fuel trim A/F Compensation 1 %
Knock sensor signal Knock Correction deg
Atmospheric absolute pressure signal Atmospheric pressure mmHg, kPa, inHg or psi
Intake manifold relative pressure signal Mani. Relative Pressure mmHg, kPa, inHg or psi
Intake manifold absolute pressure signalIntake manifold absolute pres-
suremmHg, kPa, inHg or psi
A/F correction (short term fuel trim) by rear oxygen sensor A/F Compensation 3 %
Long term whole fuel trim A/F learning 1 %
Front oxygen (A/F) sensor heater current Front O2 heater current value A
Rear oxygen sensor heater current Rear O2 heater current value A
Canister purge control solenoid valve duty ratio CPC Valve Duty Ratio %
Fuel level signal Fuel level voltage V
Intake air temperature signal Intake air temperature°C or (°F)
Learned ignition timing Ignition learning value deg
EGR signal EGR Steps STEP
Ignition switch signal Ignition SW ON or OFF
Test mode connector signal Test mode signal ON or OFF
Neutral position switch signal Neutral SW ON or OFF
Air conditioning switch signal A/C SW ON or OFF
Air conditioning compressor signal A/C Compressor Signal ON or OFF
Radiator main fan relay signal Radiator fan relay 1 ON or OFF
Fuel pump relay signal Fuel pump relay ON or OFF
Knocking signal Knock signal ON or OFF
Radiator sub fan relay signal Radiator fan relay 2 ON or OFF
Power steering switch signal Power steering SW input signal ON or OFF
Engine torque control signal #1 AT coordinate request signal 1 ON or OFF
Engine torque control signal #2 AT coordinate request signal 2 ON or OFF