2003 SUBARU IMPREZA air filter

Climate control
4-13
– CONTINUED –
Air filtration system (if equipped) If your vehicle ’s air conditioning system is equipped
with an air filtration system, replace the filter element
according to the replacement schedule shown
below. This schedule should be followed to maintain the filter ’s dust collection ability. Under extremely
dusty conditions, the filter should be replaced more
frequently. It is recommended that you have your fil-
ter checked or replaced by your SUBARU dealer.
For replacement, use only a genuine SUBARU air fil-ter kit.
Replacement schedule: Every 12 months or 7,500 miles (12,000 km) whichever comes first
NOTE The filter can influence the air conditioning, heat- ing and defroster performance if not properlymaintained.

11
11-1
– CONTINUED –
Maintenance schedule 11-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance precautions 11-3 . . . . . . . . . . . . . . . . . . . . . . . .
Engine hood 11-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine compartment overview 11-8 . . . . . . . . . . . . . . . . .
2.5 liter model 11-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.0 liter (Turbo) model 11-9 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine oil 11-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the oil level 11-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Changing the oil and oil filter 11-11 . . . . . . . . . . . . . . . . . . .
Recommended grade and viscosity 11-13 . . . . . . . . . . .
Recommended grade and viscosity under
severe driving conditions 11-15 . . . . . . . . . . . . . . . . . . . . . .
Synthetic oil 11-15
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cooling system 11-15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cooling fan, hose and connections 11-16 . . . . . . . . . . . .
Engine coolant 11-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air cleaner element 11-20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing the air cleaner element 11-20 . . . . . . . . . . . . . .
Spark plugs 11-23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommended spark plugs 11-24 . . . . . . . . . . . . . . . . . . . . .
Drive belts 11-24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Manual transmission oil 11-25 . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the oil level 11-25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommended grade and viscosity 11-26 . . . . . . . . . . .
Automatic transmission fluid 11-27 . . . . . . . . . . . . . . . . . . .
Checking the fluid level 11-27 . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommended fluid 11-29 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Front differential gear oil (AT vehicles) 11-29
. . . . .
Checking the oil level 11-29 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommended grade and viscosity 11-30 . . . . . . . . . . .
Rear differential gear oil 11-31 . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the gear oil level 11-31 . . . . . . . . . . . . . . . . . . . . . . .
Recommended grade and viscosity 11-32 . . . . . . . . . . .
Power steering fluid 11-32 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the fluid level 11-32 . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommended fluid 11-33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brake fluid 11-34 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the fluid level 11-34 . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommended brake fluid 11-34 . . . . . . . . . . . . . . . . . . . . . . .
Clutch fluid (MT vehicles) 11-35 . . . . . . . . . . . . . . . . . . . . . . . .
Checking the fluid level 11-35 . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommended clutch fluid 11-36 . . . . . . . . . . . . . . . . . . . . . .
Brake booster 11-36 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brake pedal 11-37 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the brake pedal free play 11-37 . . . . . . . . . . . .
Checking the brake pedal reserve distance 11-37 . .
Clutch pedal (MT vehicles) 11-38 . . . . . . . . . . . . . . . . . . . . . .
Checking the clutch function 11-38 . . . . . . . . . . . . . . . . . . . .
Checking the clutch pedal free play 11-38 . . . . . . . . . . .
Replacement of brake pad and lining 11-39 . . . . . . . .
Breaking-in of new brake pads and linings 11-39 . . .
Parking brake stroke 11-40 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tires and wheels 11-41 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Types of tires 11-41 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance and service

Maintenance and service
11-4
Always be very careful to avoid injury when
working on the vehicle. Remember that some of the materials in the vehicle may be hazard-
ous if improperly used or handled, for exam-ple, battery acid. Your vehicle should only be serviced by per-
sons fully competent to do so. Serious per-sonal injury may result to persons not experi-enced in servicing vehicles. Always use the proper tools and make cer-
tain 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 airbag system or seatbelt pretensioner sys-tem, or attempt to take its connectors apart,as that may activate the system or it can ren-der it inoperative. The wiring and connectorsof these systems are yellow for easy identifi-cation. NEVER use a circuit tester for these wiring. If your SRS airbag or seatbelt pretensionerneeds service, consult your nearest SUBARU
dealer.
Before checking or servicing in the
engine 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 theengine 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

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.