Subaru IMPREZA GD 2007 Series Manual page 1469

asieps_tobira_IM_US.book 138 ページ ２０１２年１月１７日 火曜日 午後３時４８分
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
6 CHECK EXHAUST SYSTEM.
Check exhaust system parts.
NOTE:
Check the following items.
• Loose part and incomplete installation of ex-
haust system
• Damage (crack, hole etc.) of parts
• Loose part and improper installation between
front oxygen (A/F) sensor and rear oxygen sensor
AH:DTC P0171 SYSTEM TOO LEAN (BANK 1)
Refer to DTC P0172 for diagnostic procedure. <Ref. to EN(STI)(diag)-139, DTC P0172 SYSTEM TOO RICH
(BANK 1), Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
Check
Is there any fault in exhaust
system?
EN(STI)(diag)-138
Yes No
Repair or replace Replace the rear
faulty parts. oxygen sensor.
<Ref. to
FU(H4DOTC)-48,
Rear Oxygen Sen-
sor.>