2004 SUBARU IMPREZA engine

10-2
Appearance care
Appearance careExterior care !
Washing
The best way to preserve your vehicle’s beauty is fre-
quent washing. Wash the vehicle at least once a
month to avoid contamination by road grime.
Wash dirt off with a wet sponge and plenty of luke-
warm or cold water. Do not wash the vehicle with hot
water and in direct sunlight.
Salt, chemicals, insects, tar, soot and bird droppings
should be washed off by using a light detergent, as re-
quired. If you use a light detergent, make certain that
it is a neutral detergent. Do not use strong soap or
chemical detergents. All cleaning agents should be
promptly flushed from the surface and not allowed to
dry there. Rinse the vehicle thoroughly with plenty of
lukewarm water. Wipe the remaining water off with a
chamois or soft cloth.
NOTE
When having your vehicle washed in an automatic
car wash, make sure beforehand that the car wash
is of suitable type. Automatic car wash brushes or
other equipment may damage the rear wiper and
rear/roof spoiler (if equipped).
" When washing the vehicle, the brakes may
get wet. As a result, the brake stopping dis-
tance will be longer. To dry the brakes, drive the
vehicle at a safe speed while lightly pressing
the brake pedal to heat up the brakes. " Do not wash the engine compartment and
area adjacent to it. If water enters the engine air
intake, electrical parts or the power steering flu-
id reservoir, it will cause engine trouble or
faulty power steering respectively.
! Washing the underbody
Chemicals, salts and gravel used for deicing road sur-
faces are extremely corrosive, accelerating the corro-
sion of underbody components, such as the exhaust
system, fuel and brake lines, brake cables, floor pan
and fenders, and suspension.
Thoroughly flush the underbody and inside of the
fenders with lukewarm or cold water at frequent inter-
vals to reduce the harmful effects of such agents.
Mud and sand adhering to the underbody components may accelerate their corrosion.
After driving off-road or on muddy or sandy roads,
wash the mud and sand off the underbody. Carefully

11 - 1
11
Maintenance and service
Maintenance schedule ................................. 11-3
Maintenance precautions ............................ 11-3 Before checking or servicing in the engine compartment .................................................. 11-4
When you do checking or servicing in the engine compartment while the engine is
running ............................................................ 11-5
Engine hood .................................................. 11-5
Engine compartment overview ................... 11-8 2.5 liter model .................................................... 11-8
2.0 liter (Turbo) model ...................................... 11-9
2.5 liter (Turbo) model ...................................... 11-10
Engine oil ...................................................... 11-11 Checking the oil level ....................................... 11-11
Changing the oil and oil filter .......................... 11-12
Recommended grade and viscosity ................ 11-16
Recommended grade and viscosity under severe driving conditions .............................. 11-18
Synthetic oil ....................................................... 11-18
Cooling system ............................................. 11-18 Cooling fan, hose and connections ................ 11-19
Engine coolant .................................................. 11-19
Air cleaner element ...................................... 11-23 Replacing the air cleaner element ................... 11-23
Spark plugs ................................................... 11-26 Recommended spark plugs ............................. 11-27
Drive belts ..................................................... 11-27
Manual transmission oil ............................... 11-28 Checking the oil level ....................................... 11-28
Recommended grade and viscosity ................ 11-30 Automatic transmission fluid ...................... 11-31
Checking the fluid level .................................... 11-31
Recommended fluid ......................................... 11-32
Front differential gear oil (AT vehicles) ...... 11-33 Checking the oil level ....................................... 11-33
Recommended grade and viscosity ............... 11-33
Rear differential gear oil ............................... 11-34 Checking the gear oil level .............................. 11-34
Recommended grade and viscosity ............... 11-35
Power steering fluid ...................................... 11-36 Checking the fluid level .................................... 11-36
Recommended fluid ......................................... 11-37
Brake fluid ..................................................... 11-37 Checking the fluid level .................................... 11-37
Recommended brake fluid ............................... 11-38
Clutch fluid (MT vehicles) ............................ 11-38 Checking the fluid level .................................... 11-38
Recommended clutch fluid .............................. 11-39
Brake booster ................................................ 11-40
Brake pedal .................................................... 11-40 Checking the brake pedal free play ................ 11-40
Checking the brake pedal reserve distance ... 11-41
Clutch pedal (MT vehicles) ........................... 11-41 Checking the clutch function .......................... 11-41
Checking the clutch pedal free play ............... 11-42
Replacement of brake pad and lining ......... 11-42 Breaking-in of new brake pads and linings .... 11-43
Parking brake stroke .................................... 11-44
Tires and wheels ........................................... 11-44

11 - 4
Maintenance and service
the materials in the vehicle may be hazardous if
improperly used or handled, for example, bat- tery acid."
Your vehicle should only be serviced by per-
sons fully competent to do so. Serious person-
al injury may result to persons not experienced
in servicing vehicles. " Always use the proper tools and make certain
that they are well maintained. " Never get under the vehicle supported only
by a jack. Always use a safety stands to sup-
port the vehicle. " Never keep the engine running in a poorly
ventilated area, such as a garage or other
closed areas. " Do not smoke or allow open flames around
the fuel or battery. This will cause a fire. " Because the fuel system is under pressure,
replacement of the fuel filter should be per-
formed only by your SUBARU dealer. " Wear adequate eye protection to guard
against getting oil or fluids in your eyes. If
something does get in your eyes, thoroughly
wash them out with clean water. " Do not tamper with the wiring of the SRS air-
bag system or seatbelt pretensioner system, or
attempt to take its connectors apart, as that may activate the system or it can render it inop-
erative. The wiring and connectors of these
systems are yellow for easy identification. NEV-
ER use a circuit tester for these wiring.
If your SRS airbag or seatbelt pretensioner
needs service, consult your nearest SUBARU
dealer.
! Before checking or servicing in the en-
gine compartment
"Always stop the engine and set the parking
brake firmly to prevent the vehicle from mov-
ing. " Always let the engine cool down. Engine
parts become very hot when the engine is run-
ning and remain hot for some time after the en-
gine is stopped. " Do not spill engine oil, engine coolant, brake
fluid or any other fluid on hot engine compo-
nents. This may cause a fire. " Always remove the key from the ignition
switch. When the ignition switch is in the “ON”
position, the cooling fan may operate suddenly

11 - 5
Maintenance and service
– CONTINUED –
even when the engine is stopped.
! When you do checking or servicing in
the engine compartment while the en-
gine is running
A running engine can be dangerous. Keep your
fingers, hands, clothing, hair and tools away
from the cooling fan, belts and any other mov-
ing engine parts. Removing rings, watches and
ties is advisable.
Engine hood
0
To open the hood:
1. If the wiper blades are lifted off the windshield, re-
turn them to their original positions.
2. Pull the hood release knob under the instrument
panel.
HSB014BA

11 - 8
Maintenance and service
Engine compartment overview !
2.5 liter model
12 345 67
8
9
10
11
12
13
UGB505BB
1) Manual transmission oil level
gauge (MT) (page 11-28) or Dif-
ferential gear oil level gauge
(AT) (page 11-33)
2) Air cleaner element (page 11- 23)
3) Clutch fluid reservoir (page 11- 38)
4) Automatic transmission fluid lev-
el gauge (page 11-31)
5) Brake fluid reservoir (page 11-
37)
6) Windshield washer tank (page 11-54)
7) Fuse box (page 11-60)
8) Battery (page 11-58)
9) Engine oil filler cap (page 11-11)
10) Engine coolant reservoir (page 11-19)
11) Radiator cap (page 11-19)
12) Engine oil level gauge (page 11- 11)
13) Power steering fluid reservoir
(page 11-36)

11 - 9
Maintenance and service
– CONTINUED –
!2.0 liter (Turbo) model
34 5 6 7
1
2
13 12 11 10 9 8
HGB005CB
1) Manual transmission oil level gauge (MT) (page 11-28) or Dif-
ferential gear oil level gauge
(AT) (page 11-33)
2) Air cleaner element (page 11- 23)
3) Clutch fluid reservoir (page 11- 38)
4) Automatic transmission fluid lev-
el gauge (page 11-31)
5) Brake fluid reservoir (page 11-
37)
6) Windshield washer tank (page 11-54)
7) Fuse box (page 11-60)
8) Battery (page 11-58)
9) Engine oil filler cap (page 11-11)
10) Engine coolant reservoir (page 11-19)
11) Engine oil level gauge (page 11-
11)
12) Radiator cap (page 11-19)
13) Power steering fluid reservoir
(page 11-36)

11 - 1 0
Maintenance and service !
2.5 liter (Turbo) model
34 5 6
7
1
2
12 11 10 9 8
UGB070BB
1) Manual transmission oil level gauge (MT) (page 11-28)
2) Air cleaner element (page 11-
23)
3) Clutch fluid reservoir (page 11- 38)
4) Brake fluid reservoir (page 11- 37)
5) Windshield washer tank (page
11-54)
6) Fuse box (page 11-60)
7) Battery (page 11-58)
8) Engine oil filler cap (page 11-11)
9) Engine coolant reservoir (page
11-19)
10) Engine oil level gauge (page 11- 11)
11) Radiator cap (page 11-19)
12) Power steering fluid reservoir (page 11-36)

11-11
Maintenance and service
– CONTINUED –
Engine oil !Checking the oil level
Check the engine oil level at each fuel stop.
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.
3. Be sure the dipstick is correctly inserted until it
stops with the graphic symbol on its top appear-
ing as shown in the illustration. 2.5-liter turbo models
1) Notch
2) Upper level
3) Lower level
HGB056BA
1 2
3
UGB081BB