Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 102

LU(STI)-10

Oil Pressure System

LUBRICATION

B: INSPECTION

Step

Check

Yes

No

1

CHECK COMBINATION METER.
1) Turn the ignition switch to ON (engine OFF).
2) Check other warning lights.

Does the warning light illumi-
nate?

Go to step

2.

Repair or replace
the combination
meter. <Ref. to IDI-
5, INSPECTION,
Combination Meter
System.>

2

CHECK POWER SUPPLY TO OIL PRES-
SURE SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from oil pressure
switch.
3) Turn the ignition switch to ON.
4) Measure the voltage between oil pressure
switch harness connector and chassis ground.

Connector & terminal

(E11) No. 1 (+) — Chassis ground (–):

Is the voltage 10 V or more?

Replace the oil
pressure switch.
<Ref. to LU(STI)-
22, Oil Pressure
Switch.>

Go to step

3.

3

CHECK COMBINATION METER.
1) Turn the ignition switch to OFF.
2) Remove the combination meter.
3) Measure the resistance of combination
meter.

Terminals

No. 2 — No. 19:

Is the resistance less than 10

Ω?

Repair the harness
and connector.
NOTE:

In this case, repair
the following item:
• Open circuit of
harness between
combination meter
and oil pressure
switch
• Poor contact of
combination meter
connector
• Poor contact of
oil pressure switch
connector
• Poor contact of
coupling connector

Repair or replace
the combination
meter. <Ref. to IDI-
5, INSPECTION,
Combination Meter
System.>

LU(STI)-11

Engine Oil

LUBRICATION

3. Engine Oil

A: INSPECTION

CAUTION:

If the engine oil is spilt over exhaust pipe or the

under cover, wipe it off with cloth to avoid emit-

ting smoke or causing a fire.

1) Park the vehicle on a level surface.

2) Remove the oil level gauge and wipe away the

oil.

3) Reinsert the oil level gauge all the way. Be sure

that the oil level gauge is correctly inserted and

properly orientated.

4) Pull out the oil level gauge again, and check the

oil level. If the engine oil level is below “L” line,

make sure that there is no oil leakage from the en-

gine, then add oil to raise the level up to the “F” line.

5) Start the engine, and spread the oil in engine

room.

6) After turning off the engine, wait a few minutes

for the oil to return to the oil pan before checking

the level.
NOTE:

• Just after driving or while the engine is warm, en-

gine oil level shows in the range between the “F”

line and the notch mark. This is caused by thermal

expansion of engine oil.

• To prevent overfilling of engine oil, do not add oil

above “F” line when the engine is cold.

• As the oil level gauge is used for daily mainte-

nance, “F” line and “L” line is set assuming that the

engine is cold.

B: REPLACEMENT

CAUTION:

If the engine oil is spilt over exhaust pipe or the

under cover, wipe it off with cloth to avoid emit-

ting smoke or causing a fire.

1) Open the engine oil filler cap for quick draining of

engine oil.

2) Lift up the vehicle.

3) Drain engine oil by loosening the engine oil drain

plug.
NOTE:

Prepare the container for draining of engine oil.

4) Tighten the engine oil drain plug after draining

engine oil.
NOTE:

Use a new drain plug gasket.
Tightening torque:

46.5 N·m (4.7 kgf-m, 34.3 ft-lb)

5) Lower the vehicle.

6) Using engine oil of proper quality and viscosity,

fill engine oil through the filler duct to the “F” line on

the oil level gauge. Make sure that the vehicle is

parked on a level surface when checking oil level.
Recommended oil:

Refer to “SPECIFICATION” for recommended

oil. <Ref. to LU(STI)-2, SPECIFICATION, Gen-

eral Description.>

Engine oil capacity:

Refer to “SPECIFICATION” for engine oil ca-

pacity. <Ref. to LU(STI)-2, SPECIFICATION,

General Description.>

(A) Oil level gauge
(B) Engine oil filler cap

(C) “F” line
(D) “L” line

(E) Approx. 1.0 L (1.1 US qt, 0.9 Imp qt)

(F) Notch mark

(C)

(F)

(B)

(A)

(E)

(D)

PM-00362

LU-02395

LU-02395

LU(STI)-12

Engine Oil

LUBRICATION

7) Close the engine oil filler cap.

8) Start the engine to circulate the oil in engine.

9) After stopping the engine, recheck the oil level. If

necessary, add engine oil up to the “F” line on oil

level gauge.

(A) Oil level gauge
(B) Engine oil filler cap

(C) “F” line
(D) “L” line

(E) Approx. 1.0 L (1.1 US qt, 0.9 Imp qt)

(F) Notch mark

(C)

(F)

(B)

(A)

(E)

(D)

PM-00362

LU(STI)-13

Oil Pump

LUBRICATION

4. Oil Pump

A: REMOVAL

1) Disconnect the ground cable from battery.

2) Remove the radiator. <Ref. to CO(STI)-19, RE-

MOVAL, Radiator.> <Ref. to CO(w/o STI)-19, RE-

MOVAL, Radiator.>

3) Lift up the vehicle.

4) Remove the bolt (B) which secures oil cooler

pipe (A) to oil pump. (Model with oil cooler)

5) Remove the oil cooler pipe (A) and hose (C).

(Model with oil cooler)

6) Lower the vehicle.

7) Remove the crankshaft position sensor.

<Ref. to FU(STI)-35, REMOVAL, Crankshaft Posi-

tion Sensor.> <Ref. to FU(w/o STI)-35, REMOVAL,

Crankshaft Position Sensor.>

8) Remove the water pump. <Ref. to CO(STI)-15,

REMOVAL, Water Pump.> <Ref. to CO(w/o STI)-

15, REMOVAL, Water Pump.>

9) Remove the crank sprocket. <Ref. to ME(STI)-

60, REMOVAL, Crank Sprocket.> <Ref. to ME(w/o

STI)-58, REMOVAL, Crank Sprocket.>

10) Remove the bolts which install oil pump onto

cylinder block.
NOTE:

When disassembling and checking the oil pump,

loosen the relief valve plug before removing the oil

pump.

11) Remove the oil pump by using flat tip screw-

driver.
CAUTION:

Be careful not to scratch mating surfaces of

cylinder block and oil pump.

12) Remove the front oil seal from the oil pump.

IN-00203

LU-02396

(B)

(C)

(C)

(A)

LU-00015

LU-00016