Subaru 2002 IMPREZA Service Manual page 990

FUEL INJECTION (FUEL SYSTEMS)
16.Front Oxygen (A/F) Sensor
A: REMOVAL
1) Disconnect the ground cable from battery.
2) Remove the solenoid valve cover.
3) Disconnect the connector from front oxygen
(A/F) sensor.
4) Disconnect the engine harness fixed by clip (A)
from the bracket (B).
5) Remove the front right side wheel.
6) Lift-up the vehicle.
FRONT OXYGEN (A/F) SENSOR
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7) Remove the service hole cover.
8) Apply SUBARU CRC or its equivalent to the
threaded portion of front oxygen (A/F) sensor, and
leave it for 1 minute or more.
SUBARU CRC (Part No. 004301003)
9) Remove the front oxygen (A/F) sensor.
CAUTION:
When removing the oxygen (A/F) sensor, wait
until the exhaust pipe cools, otherwise it will
damage exhaust pipe.
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