Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual - part 131

FU(w/o STI)-51

Wastegate Control Solenoid Valve

FUEL INJECTION (FUEL SYSTEMS)

15.Wastegate Control Solenoid 

Valve

A: REMOVAL

1) Remove the collector cover.

2) Disconnect the ground cable from battery.

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

gate control solenoid valve.

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

hose (C) from the wastegate control solenoid valve.

5) Remove  the  wastegate  control  solenoid  valve

from the bracket.

B: INSTALLATION

Install in the reverse order of removal.
Tightening torque:

6.4 N·m (0.7 kgf-m, 4.7 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-05739

(C)

(A)

(B)

Terminal No.

Standard

1 and 2

28±2 Ω (when 20°C (68°F))

2 1

EC-02426

FU-04069

(A)

(B)

FU(w/o STI)-52

Wastegate Control Solenoid Valve

FUEL INJECTION (FUEL SYSTEMS)

4) Connect the battery positive terminal to the ter-

minal No. 1 and the battery negative 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(w/o STI)-53

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) Remove the air intake duct (rear) and air cleaner

case. <Ref. to IN(w/o STI)-10, REMOVAL, Air In-

take Duct.> <Ref. to IN(w/o STI)-8, REMOVAL, Air

Cleaner Case.>

3) Disconnect the connectors from front oxygen (A/F)

sensor.

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.

5) Connect  the  connector  of  front  oxygen  (A/F)

sensor.

6) Install the air intake duct (rear) and air cleaner

case. <Ref. to IN(w/o STI)-8, INSTALLATION, Air

Cleaner Case.> <Ref. to IN(w/o STI)-10, INSTAL-

LATION, Air Intake Duct.>

IN-00203

FU-05717

FU-04624

FU-04624

FU-05717

FU(w/o STI)-54

Front Oxygen (A/F) Sensor

FUEL INJECTION (FUEL SYSTEMS)

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.

Terminal No.

Standard

2 and 4

2.4±0.24 Ω 

(when 20°C (68°F))

IN-00203

2 1
4 3

FU-05147