2004 SUBARU IMPREZA WRX service

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Maintenance and service
– CONTINUED –
7. Put the radiator cap back on and tighten firmly. At
this time, make sure that the rubber gasket in the radi-
ator cap is correctly in place.
8. Start and run the engine for more than five minutes
at 2,000 to 3,000 rpm.
9. Stop the engine and wait until the coolant cools
down (122 to 140 °F [50 to 60 °C]). If there is any loss
of coolant, add coolant to the radiator’s filler neck and
to the reserve tank’s “FULL” level.
10.Put the radiator cap and reservoir cap back on and
tighten firmly.Air cleaner element
The air cleaner element functions as a filter screen.
When the element is perforated or removed, engine
wear will be excessive and engine life shortened.
The air cleaner element is a viscous type. It is unnec-
essary to clean or wash the element.
Do not operate the engine with the air cleaner
element removed. The air cleaner element not
only filters intake air but also stops flames if the
engine backfires. If the air cleaner element is
not installed when the engine backfires, you
could be burned.
! Replacing the air cleaner element
! Non-turbo models
Replace the air cleaner element according to the
maintenance schedule in the “Warranty and Mainte-
nance Booklet”. Under extremely dusty conditions, re-
place it more frequently. It is recommended that you
always use genuine SUBARU parts.

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Maintenance and service
0
1) Bolt
1. Remove the bolt securing the rear air cleaner ele- ment case.
2. Unsnap the three clamps holding the rear air clean-
er element case. 1) Air cleaner element
3. Separate the rear air cleaner element case from
the front cleaner element case and remove the air
cleaner element.
4. Clean the inside of the front and rear air cleaner el-
ement cases with a damp cloth and install a new air
cleaner element.
5. Insert the four projections on the rear air cleaner el-
ement case into the slits on the front air cleaner ele-
ment case and snap the three clamps on the rear air
cleaner element case and then tighten the bolt.
1
HSB030BB1HSB031BB

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Maintenance and service
– CONTINUED –
!Turbo models
1. Unsnap the two clamps holding the air cleaner case cover. 1) Air cleaner case cover
2) Air cleaner element
2. Open the air cleaner case cover and remove the air
cleaner element.
3. Clean the inside of the air cleaner cover and case
with a damp cloth and install a new air cleaner ele-ment.
USB521BA
2 1
USB522BB

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Maintenance and service
4. To install the air cleaner case cover, insert the two
projections on the air cleaner case cover into the slits
on the air cleaner case and then snap the two clamps
on the air cleaner case cover.
Spark plugs
It may be difficult to replace the spark plugs. It is rec-
ommended that you have the spark plugs replaced byyour SUBARU dealer.
The spark plugs should be replaced according to the
maintenance schedule in the “Warranty and Mainte-
nance Booklet”.
"
When disconnecting the spark plug cables,
always grasp the spark plug cap, not the ca-
USB523BA
HSB032BA

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Maintenance and service
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bles. "Make sure the cables are replaced in the cor-
rect order.
! Recommended spark plugs
Non-turbo models:
RC10YC4 (Champion)
BKR6E-11 (NGK)
BKR5E-11 (NGK)
2.0-liter turbo models: PFR6G (NGK)
2.5-liter turbo models:
IFLR6B (NGK)
Drive belts
1) Power steering pump pulley
2) Air conditioner compressor pulley
3) Crank pulley
The alternator, power steering pump, and air condi-
tioner compressor depend on drive belts. Satisfactory
performance requires that belt tension be correct.
To check belt tension, place a straightedge (ruler)
across two adjacent pulleys and apply a force of 22 lb
(98 N, 10 kg) midway between the pulleys by using a
spring scale. Belt deflection should be the amount
specified. If a belt is loose, cracked, or worn, contact
2
3 A
B
1
HSB033BB

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Maintenance and service
your SUBARU dealer.
in (mm)Manual transmission oil !Checking the oil level
5 speed transmission (Non-turbo model)
1) Yellow handle
Deflection
New belt Used belt
A 0.28 — 0.35 (7.0 — 9.0) 0.35 — 0.43 (9.0 — 11.0)
B 0.30 — 0.33 (7.5 — 8.5) 0.35 — 0.40 (9.0 — 10.0)
HGB056DB
1

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Maintenance and service
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5 speed transmission (Turbo model) 6 speed transmission
1. Park the vehicle on a level surface and stop the en-
gine.
2. Pull out the dipstick, wipe it clean, and insert it
again.
HGB055BAUGB548CA

11 - 3 0
Maintenance and service
1) Upper level
2) Lower level
3. Pull out the dipstick again and check the oil level on
it. If it is below the lower level, add oil through the dip-
stick hole to bring the level up to the upper level. ! Recommended grade and viscosity
Each oil manufacturer has its own base oils and addi-
tives. Never use different brands together.
Oil grade:
API classification GL-5 SAE viscosity No. and Applicable Temperature
L
F
F
L1
2 1
2
USB526BB
-30 -20 -10 0 10 20 30 40-20 0 60 20
80W
75W/90 80 100
40
85W 90
HSB036BA