2004 SUBARU IMPREZA spark plugs

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 - 2 6
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

11 -2 7
Maintenance and service
– CONTINUED –
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

12-3
Specifications
– CONTINUED –
!Engine
! Electrical system
AT: Automatic transmission
MT: Manual transmission
Engine modelEJ251(2.5-liter, SOHC, non-turbo)EJ205 (2.0-liter, DOHC, turbo)EJ257 (2.5-liter, DOHC, turbo)
Engine typeHorizontally opposed, liquid cooled 4 cylinder, 4-stroke gasoline engine
Displacement cu in. (cc)150 (2,457)122 (1,994)150 (2,457)
Bore × Stroke in. (mm)3.9 × 3.1 (99.5 × 79.0)3.6 × 2.9 (92.0 × 75.0)3.9 × 3.1 (99.5 × 79.0)
Compression ratio10.0 : 18.0 : 18.2 : 1
Firing order1 – 3 – 2 – 4
Battery type and
capacity (5HR)MT12V-48AH (55D23L)
ATWith 2.5-liter engine12V-52AH (75D23L)
With 2.0-liter turbo engine12V-52AH (65D23L)
Alternator2.5-liter and 2.0-liter turbo engine12V – 75A
2.5-liter turbo engine12V – 90A
Spark plugs2.5-liter engineRC10YC4 (Champion)
BKR6E-11 (NGK)
BKR5E-11 (NGK)
2.0-liter turbo enginePFR6G (NGK)
2.5-liter turbo engineIFLR6B (NGK)

14-7
Index
Windows
.................................................................... 2-22
Printed antenna ............................................................ 5-2
R
Rear Combination lights ................................................ 11-74
Differential gear oil ................................................ 11-34
Differential oil temperature warning light .....3-22
Gate ............................................................................ 2-29
Seats ........................................................................... 1-8
Rear seat
Folding down (Wagon) ........................................ 1-12
Rear window Defogger switch ..................................................... 3-40
Wiper and washer switch ...................................3-39
Recommended Automatic transmission fluid .............................11-32
Brake fluid ................................................................. 11-37
Clutch fluid ................................................................ 11-39
OIL grade and viscosity .........11-16, 11-18, 11-30,
11-33, 11-35
Power steering fluid .............................................. 11-37
Spark plugs .............................................................. 11-26
Remote keyless entry system ................................2-6
Replacement Brake pad and lining ............................................ 11-42
Windshield wiper blades .....................................11-55Replacing
Air cleaner element .............................................. 11-23
Battery (remote keyless entry system) .........2-9
Lost transmitters (keyless entry system) .....2-10
Replacing bulbs ............................................................ 11-64
Cargo area light ..................................................... 11-77
Dome light ................................................................ 11-77
Front fog light .......................................................... 11-73
Front turn signal light ........................................... 11-69
Headlight ................................................................... 11-66
High mount stop light ........................................... 11-78
License plate light ................................................. 11-76
Map light .................................................................... 11-77
Parking light ............................................................. 11-70
Rear combination light ........................................11-74
Trunk light ................................................................. 11-78
REV indicator light and buzzer ..............................3-12
Rocking the vehicle .................................................... 8-16
Roof rail and crossbar ............................................... 8-21
SSeat Fabric ......................................................................... 10-6
Heater ........................................................................ 1-7
Seatbelt ............................................................................ 6
Maintenance ............................................................ 1-27
Pretensioners .......................................................... 1-27

14-8
Index
Safety tips
................................................................. 1-13
Warning light and chime ...........................1-15, 3-19
Seatbelts ......................................................................... 1-13
Security system ............................................................ 2-14
Selector lever ................................................................ 7-22
Position indicator ................................................... 3-26
Semi-automatic climate control system .............4-11
Shift lock release ......................................................... 7-26
Side ventilators ............................................................. 4-3
Snow tires ....................................................................... 8-14
Sounding a panic alarm ............................................ 2-9
Spark plugs .................................................................... 11-26
Specifications ................................................................ 12-2
Speedometer .......................................................... 3-7, 3-15
SRS airbag (Supplemental Restraint
System airbag) ....................................................... 6, 1-52
SRS airbag system warning light ..........................3-20
SRS frontal airbag ....................................................... 1-56
SRS side airbag ........................................................... 1-64
Starting the engine ...................................................... 7-9
State emission testing (U.S. only) ........................7-7
Stopping the engine ................................................... 7-11
Storage compartments .............................................. 6-5
Sun visors ....................................................................... 6-4
Sun shades .................................................................... 2-33
Supplemental Restraint System airbag (SRS) 1-52
Synthetic leather upholstery ...................................10-6T
Tachometer
............................................................. 3-9, 3-16
Temperature gauge .......................................... 3-10, 3-17
Temporary spare tire .................................................. 9-3
Tie-down hooks ............................................................. 9-18
Tilt steering wheel ........................................................ 3-49
Tire Chains ......................................................................... 8-16
Inspection .................................................................. 11-45
Pressures and wear .............................................. 11-45
Replacement ............................................................ 11-50
Rotation ...................................................................... 11-50
Tires ................................................................................... 12-5
Types .......................................................................... 11-44
Tires and wheels .......................................................... 11-44
Top tether anchorages ............................................... 1-46
Towing .............................................................................. 9-17
All wheels on the ground ....................................9-21
Flat-bed truck ........................................................... 9-20
Trailer
Hitch ............................................................................. 8-25
Hitches ........................................................................ 8-34
Towing ........................................................................ 8-29
Towing tips ................................................................ 8-37
Trunk lid ............................................................................ 2-25
Release handle ....................................................... 2-26
Trunk light ........................................................................ 11-78