SUBARU IMPREZA WRX 2003 2.G Owners Manual

Maintenance and service
11-18
WARNING
Never attempt to remove the radiator cap until the engine has been shut off and has cooled
down completely. Since the coolant is underpressure, you may suffer serious burns from a
spray of boiling hot coolant when the cap is removed.
4. Install the under cover.
Non-turbo models
1) Filler neck
2) Fill up to this level
Turbo models
1) Filler neck
2) Fill up to this level
5. Slowly pour the coolant and fill to the radiator fill-
er neck. Do not pour the coolant too quickly, as this
may lead to insufficient air bleeding and trapped airin the system.

Maintenance and service
11-19
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Guideline of coolant quantity (including coolant in reser- voir tank):
Non-turbo models: MT. 7.4 US qt (7.0 liters, 6.2 Imp qt)
AT. 7.3 US qt (6.9 liters, 6.1 Imp qt)
Turbo models: MT. 8.1 US qt (7.7 liters, 6.8 Imp qt)
AT. 8.0 US qt (7.6 liters, 6.7 Imp qt)
1) “FULL” level mark
2) “LOW” level mark
CAUTION
Be careful not to spill engine coolant when
adding it. If coolant touches the exhaust pipe, it may cause a bad smell, smoke, and/or a fire. Do not splash the engine coolant over
painted parts. The alcohol contained in the en-gine coolant may damage the paint surface.
6. Pour the coolant and fill to the reservoir tank ’s
“FULL” level mark.
1) Rubber gaskets
7. Put the radiator cap back on and tighten firmly. At

Maintenance and service
11-20
this time, make sure that the rubber gasket in the ra-
diator cap is correctly in place.
8. Start and run the engine for more than five min-utes at 2,000 to 3,000 rpm.
9. Stop the engine and wait until the coolant coolsdown (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 un-
necessary to clean or wash the element.
WARNING
Do not operate the engine with the air cleaner
element removed. The air cleaner element notonly filters intake air but also stops flames ifthe engine backfires. If the air cleaner elementis not installed when the engine backfires, youcould 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,
replace it more frequently. It is recommended that
you always use genuine SUBARU parts.

Maintenance and service
11-21
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1) Bolt
1. Remove the bolt securing the rear air cleaner ele-
ment case.
2. Unsnap the three clamps holding the rear air
cleaner 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
element cases with a damp cloth and install a new air cleaner element.
5. Insert the four projections on the rear air cleaner
element case into the slits on the front air cleaner
element case and snap the three clamps on the rearair cleaner element case and then tighten the bolt.

Maintenance and service
11-22
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 element.

Maintenance and service
11-23
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4. To install the air cleaner case cover, insert the two
projections on the air cleaner case cover into theslits 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
recommended that you have the spark plugs re-
placed by your SUBARU dealer.
The spark plugs should be replaced according to
the maintenance schedule in the
“Warranty and
Maintenance Booklet ”.

Maintenance and service
11-24
CAUTION
When disconnecting the spark plug cables,
always grasp the spark plug cap, not the cables. Make sure the cables are replaced in the
correct order.
Recommended spark plugs
Non-turbo models: RC10YC4 (Champion) BKR6E-11 (NGK)
BKR5E-11 (NGK)
Turbo models: PFR6G (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. Satisfacto-
ry 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 us- ing a spring scale. Belt deflection should be the
amount specified. If a belt is loose, cracked, or

Maintenance and service
11-25
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worn, contact your SUBARU dealer.
in (mm)
Deflection
New beltUsed belt
A0.28 — 0.35
(7.0 — 9.0)0.35 — 0.43
(9.0 — 11.0)
B0.30 — 0.33
(7.5 — 8.5)0.35 — 0.40
(9.0 — 10.0)
Manual transmission oil Checking the oil level
Non-turbo model
1) Yellow handle

Maintenance and service
11-26
Turbo model
Check the oil level monthly.
1. Park the vehicle on a level surface and stop theengine.
2. Pull out the dipstick, wipe it clean, and insert itagain.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 thedipstick hole to bring the level up to the upper level. Recommended grade and viscosity
Each oil manufacturer has its own base oils and ad-
ditives. Never use different brands together.
Oil grade: API classification GL-5

Maintenance and service
11-27
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SAE viscosity No. and Applicable Temperature Automatic transmission fluid
Checking the fluid level
The automatic transmission fluid expands largely as
its temperature rises; the fluid level differs according
to fluid temperature. Therefore, there are two differ-ent scales for checking the level of hot fluid andcold fluid on the dipstick.
Though the fluid level can be checked without
warming up the fluid on the “COLD” range, we rec-
ommend checking the fluid level when the fluid is at
operating temperature.
Checking the fluid level when the fluid is hot
Check the fluid level monthly.
1. Drive the vehicle several miles to raise the tem-
perature of the transmission fluid up to normal oper-
ating temperature; 158 to 176 °F (70 to 80 °C) is nor-
mal.
2. Park the vehicle on a level surface and set theparking brake.
3. First shift the selector lever in each position. Then shift it in the “P” position, and run the engine at id-
ling speed.