2004 SUBARU FORESTER spark plugs replace

PM-4
PERIODIC MAINTENANCE SERVICE
Schedule
2. EXCEPT FOR EUROPE AREA
For periodic maintenance of over 50,000 km (30,000 miles) or 48 months, carry out inspections by referring
to the following tables. For a maintenance period gone beyond these tables, apply them repeatedly as a set
of 50,000 km (30,000 miles) or 48 months.
For periodic maintenance of over 100,000 km (60,000 miles) or 48 months, carry out inspections by referring
to the following tables. For a maintenance period gone beyond these tables, apply them repeatedly as a set
of 100,000 km (60,000 miles) or 48 months.
Symbols used:
R: Replace
I: Inspection
(I): Recommended service for safe vehicle operation.
N
OTE:
(1) When the vehicle is used in extremely dusty conditions, the air cleaner element should be replaced more often.
(2) ATF filter is a maintenance free part. ATF filter needs replacement, when it is physically damaged or ATF leaked.Maintenance Interval
[Number of months or km (miles), whichever occurs first]
Months 12 24 36 48
Remarks ×1,000 km 5 12.5 25 37.5 50
×1,000 miles 3 7.5 15 22.5 30
1 Engine oil R R R R
2 Engine oil filter R R R R
Maintenance Interval
[Number of months or km (miles), whichever occurs first]
Months 12 24 36 48
Remarks ×1,000 km 1.6 25 50 75 100
×1,000 miles 1 15 30 45 60
3 Spark plugs For Turbo R
Others R R R R
4Drive belt(s) IIII
5 Camshaft drive belt R
6 Fuel line I I
7 Fuel filter R R
8 Air cleaner element I R I R
9 Cooling system I I
10 Coolant R R
11 Clutch system I I I I I
12 Hill-holder system I I I I I
13 Transmission oil R R
14 ATF R R
15 Front & rear differential oil R R
16 Brake line I I
17 Brake fluid R R
18 Disc brake pads & discs I I I I
19 Brake linings and drums I I
20 Parking brake I I I I
21 Suspension I I I I
22 Wheel bearing (I)
23 Axle boots & joints I I I I
24 Steering system (Power steering) I I I I

PM-10
PERIODIC MAINTENANCE SERVICE
Spark Plugs
5. Spark Plugs
A: REPLACEMENT
1) Remove the intake duct and intake chamber.
2) Remove the washer tank and put it aside.
3) Disconnect the spark plug cord.
4) Remove the spark plug with a plug-wrench.
5) Set the new spark plug.
Spark plug:
Non-turbo model
CHAMPION RC10YC4 (Standard)
NGK BKR5E-11 (Alternate)
2.0 L Turbo model
NGK PFR6G
2.5 L Turbo model
NGK ILFR6B
Spark plug gap:
Non-turbo model
1.0 — 1.1 mm (0.039 — 0.043 in)
Turbo model
0.7 — 0.8 mm (0.028 — 0.031 in)
6) Tighten the spark plug lightly with hand, and
then secure with a plug-wrench to the specified
torque.
Tightening torque:
21
±3 N·m (2.14±0.31 kgf-m, 15.49±2.21 ft-lb)
NOTE:
 Be sure to place the gasket between the cylinder
head and spark plug.
 If a torque wrench is not available, tighten the
spark plug until gasket contacts cylinder head; then
tighten further 1/4 to 1/2 turns.
PM-00001

IG(H4SO)-6
IGNITION
Spark Plug
6) Remove the spark plugs with spark plug sock-
ets.
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)
NOTE:
The above torque should be only 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.
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)
NOTE:
The above torque should be only 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.
C: INSPECTION
Check the electrodes and inner and ceramic insu-
lator of plugs, noting the type of deposits and the
degree of electrode erosion.
1) Normal:
Brown to grayish-tan deposits and slight electrode
wear indicates 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
city, weak ignition, too rich fuel mixture, dirty air
cleaner, etc.
It is advisable to replace with plugs having hotter
heat range.
IG-00022
(A) Electrode gap
(B) Carbon accumulation or wear
(C) Cracks
(D) Damage
(E) Damaged gasket
IG-00023
(A)
(B)
(C)
(D)
(E)
IG-00024
IG-00025

IG(H4SO)-7
IGNITION
Spark Plug
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 gray
brown spots and bluish burnt electrodes indicates
engine overheating. Moreover, the appearance re-
sults 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.
D: CLEANING
Clean the spark plugs in a sand blast type cleaner.
Avoid excessive blasting. Clean and remove the
carbon or oxide deposits, but do not wear away ce-
ramic insulator.
If deposits are too stubborn, replace the spark
plugs.
E: ADJUSTMENT
Correct it if the spark plug gap is measured with a
gap gauge, and it is necessary.
Spark plug gap: L
1.0 — 1.1 mm (0.039 — 0.043 in)
NOTE:
Replace with a new spark plug if this area (A) is
worn to “ball” shape.
IG-00026
IG-00027
IG-00028
L
(A)

IG(H4DOTC)-7
IGNITION
Spark Plug
2) Carbon fouled:
Dry fluffy carbon deposits on insulator and elec-
trode are mostly caused by slow speed driving in
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 gray
brown spots and bluish burnt electrodes indicates
engine overheating. Moreover, the appearance re-
sults 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.D: ADJUSTMENT
Clean the spark plugs with a wire brush. Clean and
remove the carbon or oxide deposits, but do not
wear 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 spark plug cleaners, because the spark
plugs are applied with platinum or irigium tips.
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-00012
IG-00013
IG-00014
IG-00015
L
(A)