Subaru Legacy 2002 Service Manual page 969

Fuel Injection (Fuel Systems)
7) Remove front oxygen (A/F) sensor.
CAUTION:
When removing front oxygen (A/F) sensor, do
not force front oxygen (A/F) sensor especially
when exhaust pipe is cold, otherwise it will
damage exhaust pipe.
FRONT OXYGEN (A/F) SENSOR
B2M4524
B2M4525
FU(H6)-44
B: INSTALLATION
1) Before installing front oxygen (A/F) sensor,
apply anti-seize compound only to threaded por-
tion of front oxygen (A/F) sensor to make the next
removal easier.
Anti-seize compound:
SS-30 by JET LUBE
CAUTION:
Never apply anti-seize compound to protector
of front oxygen (A/F) sensor.
2) Install front oxygen (A/F) sensor.
Tightening torque:
21 N·m (2.1 kgf-m, 15.2 ft-lb)
S145642A11
B2M4524
B2M4525