Subaru FORESTER 2001 Service Manual page 160

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
No.
1 CHECK ANY OTHER DTC ON DISPLAY.
Step
Does the Subaru Select
Monitor or OBD-II general
scan tool indicate DTC
P0136?
EN(DOHC TURBO)-159
Check Yes
Inspect DTC
P0136 using "List
of Diagnostic
Trouble Code
(DTC)". <Ref. to
EN(DOHC
TURBO)-82, List
of Diagnostic
Trouble Code
(DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0139.
Engine (Diagnostics)
No
Replace rear oxy-
gen sensor. <Ref.
to FU(DOHC
TURBO)-44, Rear
Oxygen Sensor.>