Subaru Legacy III (2000-2003 year). Manual - part 293

IG(H6DO)-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:

NGK: PLFR6A-11

1. RH SIDE

1) Disconnect battery ground cable.

2) Remove air cleaner lower case. <Ref. to
IN(H6DO)-5, REMOVAL, Air Cleaner.>
3) Disconnect connector from ignition coil.
4) Remove ignition coil.

5) Remove spark plugs with the spark plug socket.

2. LH SIDE

1) Disconnect battery cables and then remove bat-
tery and battery carrier.

2) Disconnect washer motor connector.

3) Remove the two bolts which hold the washer
tank, then take the tank away from the working ar-
ea.

4) Disconnect connector from ignition coil.
5) Remove ignition coil.

FU-00009

IG-00053

IG-00054

IG-00055

IG-00056

IG-00057

IG-00058

IG(H6DO)-5

IGNITION

SPARK PLUG

6) Remove spark plug with the spark plugs 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 ft-lb)

CAUTION:
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 approximately 1/3 of the
specified torque in order to avoid over-stress-
ing.

Tightening torque (Ignition coil):

16 N·m (1.6 kgf-m, 12 ft-lb)

2. LH SIDE

Install in the reverse order of removal.

Tightening torque (Spark plug):

21 N·m (2.1 kgf-m, 15 ft-lb)

CAUTION:
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 approximately 1/3 of the
specified torque in order to avoid over-stress-
ing.

Tightening torque (Ignition coil):

16 N·m (1.6 kgf-m, 12 ft-lb)

C: INSPECTION

Check the electrodes and inner and outer porcelain
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-00059

(A) Electrode gap

(B) Carbon accumulation or wear

(C) Cracks

(D) Damage

(E) Damaged gasket

IG-00060

( D )

( B )

( C )

( E )

( A )

IG-00024

IG-00025

IG(H6DO)-6

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 spark plugs in a sand blast type cleaner.
Avoid excessive blasting. Clean and remove car-
bon or oxide deposits, but do not wear away porce-
lain.
If deposits are too stubborn, replace 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 new spark plug if this area (A) is worn
to “ball” shape.

IG-00026

IG-00027

IG-00065

L

( A )

IG(H6DO)-7

IGNITION

IGNITION COIL AND IGNITOR ASSEMBLY

3. Ignition Coil and Ignitor As-

sembly

A: REMOVAL

Direct ignition type is adopted.
For the order of removal, refer to the removal of
spark plugs.

B: INSTALLATION

Install in the reverse order of removal.

Tightening torque:

16 N·m (1.6 kgf-m, 12 ft-lb)

C: INSPECTION

Because ignition coil is a direct ignition type, the re-
sistance cannot be measured in a single unit. For
inspection procedure of ignition system, refer to the
following. <Ref. to EN(H6DO)-80, IGNITION CON-
TROL SYSTEM, Diagnostics for Engine Starting
Failure.>