Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual - part 35

FU(STI)-52

Wastegate Control Solenoid Valve

FUEL INJECTION (FUEL SYSTEMS)

15.Wastegate Control Solenoid 

Valve

A: REMOVAL

1) Disconnect the ground cable from battery.

2) Remove the vacuum hose from clip (A), and re-

move  the  bolt  (B)  which  secures  the  wastegate

control solenoid valve.

3) Remove  the  bolts  (C)  which  secure  solenoid

valve bracket onto intake manifold.

4) Disconnect  the  connector  (A)  from  the  waste-

gate control solenoid valve.

5) Disconnect the vacuum hose (B) and air control

hose (C) from the wastegate control solenoid valve,

and remove the wastegate control solenoid valve.

B: INSTALLATION

Install in the reverse order of removal.
Tightening torque:

T1: 6.4 N·m (0.7 kgf-m, 4.7 ft-lb)

T2: 19 N·m (1.9 kgf-m, 14.0 ft-lb)

C: INSPECTION

1. WASTEGATE CONTROL SOLENOID 

VALVE

1) Check that the wastegate control solenoid valve

has no deformation, cracks or other damages.

2) Check  the  resistance  between  the  wastegate

control solenoid valve terminals.

3) Check that air does not come out from (B) when

air is blown into (A).

IN-00203

FU-06585

(A)

(C)

(B)

(C)

FU-06586

(A)

(B)

(C)

Terminal No.

Standard

1 and 2

28±2 Ω (when 20°C (68°F))

FU-06587

T1

T1

T2

2 1

EC-02426

FU-04069

(A)

(B)

FU(STI)-53

Wastegate Control Solenoid Valve

FUEL INJECTION (FUEL SYSTEMS)

4) Connect the battery positive terminal to the ter-

minal No. 1 and the battery ground terminal to the

terminal  No.  2.  Check  that  air  is  discharged  from

(B), when supplying air to (A).

2. OTHER INSPECTIONS

Check that the vacuum hose and air control hose

have no cracks, damage or loose part.

FU-04070

2 1

(A)

(B)

FU(STI)-54

Front Oxygen (A/F) Sensor

FUEL INJECTION (FUEL SYSTEMS)

16.Front Oxygen (A/F) Sensor

A: REMOVAL

1) Disconnect the ground cable from battery.

2) Disconnect the connector from the front oxygen

(A/F) sensor, and remove the clip (A) holding the

return hose and front oxygen (A/F) sensor harness.

3) Remove  the  clips  (A)  holding  the  front  oxygen

(A/F) sensor harness to the engine harness stay.

4) Lift up the vehicle.

5) Remove  the  under  cover.  <Ref.  to  EI-28,  RE-

MOVAL, Front Under Cover.>

6) Apply spray-type lubricant to the threaded por-

tion of front oxygen (A/F) sensor, and leave it for

one minute or more.

7) Remove the front oxygen (A/F) sensor.
CAUTION:

When removing the front oxygen (A/F) sensor,

wait until exhaust pipe cools, otherwise it will

damage the exhaust pipe.

B: INSTALLATION

CAUTION:

If lubricant is spilt onto the exhaust pipe, wipe it

off completely with cloth to avoid emission of

smoke or causing a fire.

1) Before installing front oxygen (A/F) sensor, ap-

ply anti-seize compound only to the threaded por-

tion of front oxygen (A/F) sensor to make the next

removal easier.
CAUTION:

Never apply anti-seize compound to the protec-

tor of front oxygen (A/F) sensor.
Anti-seize compound:

NEVER-SEEZ NSN, JET LUBE SS-30 or 

equivalent

2) Install the front oxygen (A/F) sensor.
Tightening torque:

30 N·m (3.1 kgf-m, 22.1 ft-lb)

3) Install the under cover. <Ref. to EI-28, INSTAL-

LATION, Front Under Cover.>

4) Lower the vehicle.

IN-00203

FU-03602

(A)

FU-05872

(A)

FU-04607

FU-04607

FU(STI)-55

Front Oxygen (A/F) Sensor

FUEL INJECTION (FUEL SYSTEMS)

5) Secure the front oxygen (A/F) sensor harness to

the engine harness stay using the clips (A).

6) Connect the connector to the front oxygen (A/F)

sensor, and secure the return hose and front oxy-

gen (A/F) sensor harness using the clip (A).

7) Connect the battery ground terminal.

C: INSPECTION

1) Check that the front oxygen (A/F) sensor has no

deformation, cracks or other damages.

2) Measure  the  resistance  between  front  oxygen

(A/F) sensor terminals.

FU-05872

(A)

FU-03602

(A)

IN-00203

Terminal No.

Standard

1 and 2

2.4±0.24 Ω 

(when 20°C (68°F))

1 2
3 4

FU-04072