Subaru Legacy III (2000-2003 year). Manual - part 393

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FUEL INJECTION (FUEL SYSTEMS)

FRONT OXYGEN (A/F) SENSOR

13.Front Oxygen (A/F) Sensor

A: REMOVAL

1) Disconnect the ground cable from battery.

2) Disconnect the connector from front oxygen (A/
F) sensor.
3) Lift-up the vehicle.
4) Apply SUBARU CRC or its equivalent to the
threaded portion of front oxygen (A/F) sensor, and
then leave it for one minute or more.

SUBARU CRC (Part No. 004301003)
5) Remove the front oxygen (A/F) sensor.

NOTE:
When removing the oxygen (A/F) sensor, wait until
the exhaust pipe cools, otherwise it will damage the
exhaust pipe.

B: INSTALLATION

1) Before installing the front oxygen (A/F) sensor,
apply anti-seize compound only to the threaded
portion of front oxygen (A/F) sensor to make the
next removal easier.

Anti-seize compound:

SS-30 by JET LUBE

NOTE:
Never apply anti-seize compound to the protector
of front oxygen (A/F) sensor.

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

Tightening torque:

21 N·m (2.1 kgf-m, 15.2 ft-lb)

3) Lower the vehicle.
4) Connect the connector of front oxygen (A/F)
sensor.
5) Connect the battery ground cable to battery.

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FUEL INJECTION (FUEL SYSTEMS)

REAR OXYGEN SENSOR

14.Rear Oxygen Sensor

A: REMOVAL

1) Disconnect the ground cable from battery.

2) Lift-up the vehicle.
3) Disconnect the connector from rear oxygen sen-
sor.

4) Apply SUBARU CRC or its equivalent to the
threaded portion of rear oxygen sensor, and then
leave it for one minute or more.

SUBARU CRC (Part No. 004301003)
5) Remove the rear oxygen sensor.

NOTE:
When removing the oxygen sensor, wait until the
exhaust pipe cools, otherwise it will damage the ex-
haust pipe.

B: INSTALLATION

1) Before installing the rear oxygen sensor, apply
anti-seize compound only to the threaded portion of
rear oxygen sensor to make the next removal eas-
ier.

NOTE:
Never apply anti-seize compound to the protector
of rear oxygen sensor.

Anti-seize compound:

SS-30 by JET LUBE

2) Install the rear oxygen sensor.

Tightening torque:

21 N·m (2.1 kgf-m, 15.2 ft-lb)

3) Connect the connector to rear oxygen sensor.

4) Lower the vehicle.
5) Connect the battery ground cable to battery.

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FUEL INJECTION (FUEL SYSTEMS)

ENGINE CONTROL MODULE

15.Engine Control Module

A: REMOVAL

1) Disconnect the ground cable from battery.

2) Remove the lower inner trim of passenger side.
<Ref. to EI-39, REMOVAL, Lower Inner Trim.>
3) Detach the floor mat of front passenger seat. 
4) Remove the protect cover.

5) Remove the nuts (A) which hold ECM to bracket.
6) Remove the clip (B) from bracket.

7) Disconnect the ECM connectors and take out
the ECM.

B: INSTALLATION

Install in the reverse order of removal.

NOTE:
When replacing the ECM, be careful not to use the
wrong spec. ECM to avoid any damage to the fuel
injection system.

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(A)

(A)

(B)

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FUEL INJECTION (FUEL SYSTEMS)

MAIN RELAY

16.Main Relay

A: REMOVAL

1) Disconnect the ground cable from battery.

2) Remove the lower inner trim of passenger side.
<Ref. to EI-39, REMOVAL, Lower Inner Trim.>
3) Disconnect the connectors from main relay.
4) Remove the bolt which holds main relay bracket
on body.

B: INSTALLATION

Install in the reverse order of removal.

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