Subaru 2012 Legacy User manual

FUJI HEAVY INDUSTRIES LTD. G2320GE3
2004 LEGACY SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE SECTION 2
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 SYSTEMS) FU(H4DOTC)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICES) EC(H4DOTC)
INTAKE (INDUCTION) IN(H4DOTC)
MECHANICAL ME(H4DOTC)
EXHAUST EX(H4DOTC)
COOLING CO(H4DOTC)
LUBRICATION LU(H4DOTC)
SPEED CONTROL SYSTEMS SP(H4DOTC)
IGNITION IG(H4DOTC)
STARTING/CHARGING SYSTEMS SC(H4DOTC)
ENGINE (DIAGNOSTICS) EN(H4DOTC)(diag)

IGNITION IG(H4DOTC)
Page
1. General Description ....................................................................................2
2. Spark Plug...................................................................................................4
3. Ignition Coil & Ignitor ASSY ........................................................................7

IG(H4DOTC)-2
IGNITION General Description
1. General Description
A: SPECIFICATION
B: COMPONENT
Item Specification
Ignition coil & ignitor
ASSY
Model FK0186
Ignition system Independent ignition coil
Manufacturer Diamond Electric
Spark plug
Manufacturer and type NGK: ILFR6B
Thread size (diameter, pitch, length) mm 14, 1.25, 19
Spark plug gap mm (in) 0.7 — 0.8 (0.028 — 0.031)
Electrode Iridium
(1) Spark plug Tightening torque: N
⋅ m (kgf-m, ft-lb)
(2) Ignition coil & ignitor ASSY T1: 21 (2.1, 15.2)
T2: 16 (1.6, 11.7)
IG-00098
(1)
T1
T2
T1
(1)
(2)
(2)
T2

IG(H4DOTC)-3
IGNITION
General Description
C: CAUTION
• Wear work clothing, including a cap, protective
goggle and protective shoes during operation.
• Remove contamination including dirt and corro-
sion before removal, installation or disassembly.
• Keep the disassembled parts in order and pro-
tect them from dust and dirt.
• Before removal, installation or disassembly, be
sure to clarify the failure. Avoid unnecessary re-
moval, installation, disassembly and replacement.
• Be careful not to burn yourself, because each
part on the vehicle is hot after running.
• Be sure to tighten fasteners including bolts and
nuts to the specified torque.
• Place shop jacks or rigid racks at the specified
points.
• Before disconnecting electrical connectors of
sensors or units, be sure to disconnect the ground
cable from battery.

IG(H4DOTC)-4
IGNITION Spark Plug
2. Spark Plug
A: REMOVAL
CAUTION:
All spark plugs installed on an engine must be
of the same heat range.
Spark plug:
<Ref. to IG(H4DOTC)-2, SPECIFICATION,
General Description.>
1. RH SIDE
1) Remove the collector cover.
2) Disconnect the ground cable from battery.
3) Remove the air cleaner case.
<Ref. to IN(H4DOTC)-8, REMOVAL, Air Cleaner
Case.>
4) Disconnect the connector from ignition coil.
5) Remove the ignition coil.
NOTE:
Turn the #3 ignition coil by 180°to remove it.
6) Remove the spark plug with a spark plug socket.
2. LH SIDE
1) Remove the collector cover.
2) Remove the battery and battery carrier.
3) Disconnect the connector from ignition coil.
4) Remove the ignition coil.
NOTE:
Turn the #4 ignition coil by 180°to remove it.
5) Remove the spark plug with a spark plug socket.
B: INSTALLATION
1. RH SIDE
Install in the reverse order of removal.
Tightening torque (Spark plug):
21 N
⋅ m (2.1 kgf-m, 15.2 ft-lb)
Tightening torque (Ignition coil):
16 N
⋅ m (1.6 kgf-m, 11.7 ft-lb)
NOTE:
The above torque should only be applied to new
spark plugs without oil on their threads.
In case their threads are lubricated, the torque
should be reduced by approximately 1/3 of the
specified torque in order to avoid over-stressing.
2. LH SIDE
Install in the reverse order of removal.
Tightening torque (Spark plug):
21 N
⋅ m (2.1 kgf-m, 15.2 ft-lb)
Tightening torque (Ignition coil):
16 N
⋅ m (1.6 kgf-m, 11.7 ft-lb)
NOTE:
The above torque should only be applied to new
spark plugs without oil on their threads.
In case their threads are lubricated, the torque
should be reduced by approx. 1/3 of the specified
torque in order to avoid over-stressing.
IN-00203
IG-00092
IG-00093

IG(H4DOTC)-5
IGNITION
Spark Plug
C: INSPECTION
Check the electrodes and inner and outer ceramic
insulator of plugs, noting the type of deposits and
the degree of electrode erosion.
1) Normal:
Brown to grayish-tan deposits and slight electrode
wear indicate correct spark plug heat range.
2) Carbon fouled:
Dry fluffy carbon deposits on insulator and elec-
trode are mostly caused by slow speed driving in
the city, weak ignition, too rich fuel mixture, dirty air
cleaner, etc.
It is advisable to replace with plugs having hotter
heat range.
3) Oil fouled:
Wet black deposits show excessive oil entrance
into combustion chamber through worn rings and
pistons or excessive clearance between valve
guides and stems. If the same condition remains
after repair, use a hotter plug.
4) Overheating:
White or light gray insulator with black or brown
spots and bluish burnt electrodes indicate engine
overheating. Moreover, the appearance results
from incorrect ignition timing, loose spark plugs,
wrong selection of fuel, hotter range plug, etc. It is
advisable to replace with plugs having colder heat
range.
(A) Spark plug gap
(B) Carbon accumulation or wear
(C) Crack
(D) Damage
(E) Damaged gasket
IG-0201
0
(A)
(B)
(E) (C)
(D)
IG-0001
1
IG-0001
2
IG-0001
3
IG-0001
4

IG(H4DOTC)-6
IGNITION Spark Plug
D: ADJUSTMENT
Clean the spark plugs using a wire brush.
Clean and remove the carbon or oxide deposits.
But do not wear away ceramic insulator.
If deposits are too stubborn, replace the plugs.
After cleaning the spark plugs, correct the spark
plug gap using a gap gauge.
NOTE:
Do not use a plug cleaner because the spark plugs
are applied with iridium tip.
Spark plug gap: L
0.7 — 0.8 mm (0.028 — 0.031 in)
NOTE:
Replace with a new spark plug if this area (A) is
worn to “ball” shape.
IG-0001
5
L(A)

IG(H4DOTC)-7
IGNITION
Ignition Coil & Ignitor ASSY
3. Ignition Coil & Ignitor ASSY
A: REMOVAL
Direct ignition type has been adopted. Refer to
“Spark Plug” for removal procedure. <Ref. to
IG(H4DOTC)-4, REMOVAL, Spark Plug.>
B: INSTALLATION
Install in the reverse order of removal.
Tightening torque:
16 N
⋅ m (1.6 kgf-m, 11.7 ft-lb)
C: INSPECTION
For inspection procedure, refer to “Diagnostics for
Engine Starting Failure”. <Ref. to EN(H4DOTC)(di-
ag)-48, IGNITION CONTROL SYSTEM, Diagnos-
tics for Engine Starting Failure.>

IG(H4DOTC)-8
IGNITION Ignition Coil & Ignitor ASSY