Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 59

IN(STI)-18

Turbocharger

INTAKE (INDUCTION)

12) Install the intercooler stay.
Tightening torque:

16 N·m (1.6 kgf-m, 11.8 ft-lb)

13) Install the intercooler. <Ref. to IN(STI)-13, IN-

STALLATION, Intercooler.>

14) Connect the battery ground terminal.

15) Fill engine coolant. <Ref. to CO(STI)-13, FILL-

ING OF ENGINE COOLANT, REPLACEMENT,

Engine Coolant.>

C: INSPECTION

1. WASTE GATE ACTUATOR

1) Remove the intercooler. <Ref. to IN(STI)-12,

REMOVAL, Intercooler.>

2) Remove the turbocharger upper cover.

3) Remove the boost hose (B) from the waste gate

actuator (A) of the turbocharger, and connect the

Mighty Vac to the waste gate actuator (A).

4) Pressurize slowly with the Mighty Vac, and mea-

sure the pressure when the control rod stroke (D)

becomes 2 mm (0.08 in). If it is not within the stan-

dard, replace the turbocharger assembly.
CAUTION:

Do not pressurize over 89.9 kPa (0.92 kgf/cm

2

,

13.0 psi) to prevent damaging the waste gate

actuator.
Operating pressure (control rod stroke 2 mm

(0.08 in)):

Standard

74.7 — 80.8 kPa

(0.76 — 0.82 kgf/cm

2

, 10.8 — 11.7 psi)

5) After inspection, install the related parts in the

reverse order of removal.
Tightening torque:

7.5 N·m (0.8 kgf-m, 5.5 ft-lb)

2. OTHER INSPECTIONS

1) Check that the turbocharger, turbocharger stay

and pipe have no deformation, cracks or other

damages.

2) Check that the hose and intake duct have no

cracks, damage or loose part.

3) Check that there are no oil leakage or water

leakage from the pipe attachment section.

EX-00007

IN-00203

EX-02662

(A) Waste gate actuator
(B) Boost hose

(C) Control rod
(D) Control rod stroke

(C)

(B)

(A)

IN-02942

(D)

IN(STI)-19

Air By-pass Valve

INTAKE (INDUCTION)

8. Air By-pass Valve

A: REMOVAL

Remove the air by-pass valve from the intercooler,

and then disconnect air by-pass hose (A) and vac-

uum hose (B) from the air by-pass valve.

B: INSTALLATION

Install in the reverse order of removal.
NOTE:

Use a new gasket.
Tightening torque:

16 N·m (1.6 kgf-m, 11.8 ft-lb)

C: INSPECTION

1. AIR BY-PASS VALVE

1) Check that the air by-pass valve has no defor-

mation, cracks or other damages.

2) Connect the Mighty Vac to the nipple (A) of the

air by-pass valve.

3) Using the Mighty Vac, generate the vacuum pres-

sure to –93.3 kPa (–0.95 kgf/cm

2

, –13.5 psi). Check

that the Mighty Vac gauge needle holds 10 seconds

without falling by –92.6 kPa (–0.94 kgf/cm

2

, –13.4

psi).

4) Set a dial gauge to the end of valve rod of the air

by-pass valve.

5) Slowly generate vacuum pressure with the

Mighty Vac and check the pressure when the nee-

dle of the dial gauge (valve stroke) becomes 0.5

mm (0.02 in). If it is not within the standard, replace

the air by-pass valve.
Opening pressure (valve stroke 0.5 mm (0.02

in)):

Standard

–62.7 — –70.7 kPa

(–0.64 — –0.72 kgf/cm

2

, –9.09 — –10.3 psi)

6) Increase vacuum pressure more than 5) and

check the pressure when the needle of the dial

gauge (valve stroke) becomes 7.5 mm (0.3 in). If it

is not within the standard, replace the air by-pass

valve.
Full open pressure (valve stroke 7.5 mm (0.3

in)):

Standard

–102.7 — –117.3 kPa

(–1.05 — –1.20 kgf/cm

2

, –14.9 — –17.0 psi)

2. OTHER INSPECTIONS

Check that the vacuum hose and air by-pass pipe

have no cracks, damage or loose part.

IN-03501

(B)

(A)

IN-02606

(A)

IN-02607

IN(STI)-20

Resonator Chamber

INTAKE (INDUCTION)

9. Resonator Chamber

A: REMOVAL

The resonator chamber and air cleaner case are in-

tegrated into one unit; therefore, refer to “Air Clean-

er Case” for removal procedure. <Ref. to IN(STI)-8,

REMOVAL, Air Cleaner Case.>

B: INSTALLATION

The resonator chamber and air cleaner case are in-

tegrated into one unit; therefore, refer to “Air Clean-

er Case” for installation procedure. <Ref. to

IN(STI)-8, INSTALLATION, Air Cleaner Case.>

C: INSPECTION

Check that the resonator chamber has no deforma-

tion, cracks or other damages.

MECHANICAL

ME(STI)

Page

1.

General Description . . . . . . . . . . . . . . . . . . . . ...2

2.

Compression . . . . . . . . . . . . . . . . . . . . . . . 20

3.

Idle Speed . . . . . . . . . . . . . . . . . . . . . . . . 21

4.

Ignition Timing . . . . . . . . . . . . . . . . . . . . . . ..22

5.

Intake Manifold Vacuum . . . . . . . . . . . . . . . . . . ...23

6.

Engine Oil Pressure . . . . . . . . . . . . . . . . . . . . .24

7.

Fuel Pressure . . . . . . . . . . . . . . . . . . . . . . ...25

8.

Valve Clearance . . . . . . . . . . . . . . . . . . . . . ...26

9.

Engine Assembly . . . . . . . . . . . . . . . . . . . . . .30

10.

Engine Mounting . . . . . . . . . . . . . . . . . . . . . ..38

11.

Preparation for Overhaul . . . . . . . . . . . . . . . . . . ..39

12.

V-belt . . . . . . . . . . . . . . . . . . . . . . . . . . 40

13.

Crank Pulley . . . . . . . . . . . . . . . . . . . . . . . .47

14.

Timing Belt Cover . . . . . . . . . . . . . . . . . . . . . .49

15.

Timing Belt . . . . . . . . . . . . . . . . . . . . . . . ...50

16.

Cam Sprocket . . . . . . . . . . . . . . . . . . . . . . ..59

17.

Crank Sprocket . . . . . . . . . . . . . . . . . . . . . . 60

18.

Camshaft . . . . . . . . . . . . . . . . . . . . . . . . ..61

19.

Cylinder Head . . . . . . . . . . . . . . . . . . . . . . ..70

20.

Cylinder Block . . . . . . . . . . . . . . . . . . . . . . ..80

21.

Intake and Exhaust Valve . . . . . . . . . . . . . . . . . ..103

22.

Piston . . . . . . . . . . . . . . . . . . . . . . . . . .104

23.

Connecting Rod . . . . . . . . . . . . . . . . . . . . . .105

24.

Crankshaft . . . . . . . . . . . . . . . . . . . . . . . ..106

25.

Engine Trouble in General . . . . . . . . . . . . . . . . . .107

26.

Engine Noise . . . . . . . . . . . . . . . . . . . . . . ..113