Subaru 2009 IMPREZA Service Manual page 1327

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
1 CHECK AIR INTAKE SYSTEM.
2 CHECK MANIFOLD ABSOLUTE PRESSURE
SENSOR.
1) Start the engine and warm up engine until
coolant temperature is higher than 75°C
(167°F).
2) For AT models, set the select lever to "P"
range or "N" range, and for MT models, place
the shift lever in the neutral position.
3) Turn the A/C switch to OFF.
4) Turn all the accessory switches to OFF.
5) Read the data of intake manifold absolute
pressure sensor signal using the Subaru Select
Monitor or general scan tool.
NOTE:
• Subaru Select Monitor
For detailed operation procedures, refer to
"READ CURRENT DATA FOR ENGINE". <Ref.
to EN(H4DOTC)(diag)-34, Subaru Select Moni-
tor.>
• General scan tool
For detailed operation procedures, refer to the
"General Scan Tool Instruction Manual".
3 CHECK THROTTLE OPENING ANGLE.
Read the data of throttle position signal using
Subaru Select Monitor or general scan tool.
NOTE:
• Subaru Select Monitor
For detailed operation procedures, refer to
"READ CURRENT DATA FOR ENGINE". <Ref.
to EN(H4DOTC)(diag)-34, Subaru Select Moni-
tor.>
• General scan tool
For detailed operation procedures, refer to the
"General Scan Tool Instruction Manual".
4 CHECK THROTTLE OPENING ANGLE.
Check
Are there holes, loose bolts or
disconnection of hose on air
intake system?
Is the measured value 73.3 —
106.6 kPa (550 — 800 mmHg,
21.65 — 31.50 inHg) when the
ignition is turned ON, and 20.0 —
46.7 kPa (150 — 350 mmHg,
5.91 — 13.78 inHg) during
idling?
Is the measured value less than
5% when throttle is fully
closed?
Is the measured value 85% or
more when throttle is fully
open?
EN(H4DOTC)(diag)-106
Yes No
Repair the air Go to step 2.
intake system.
Go to step 3. Replace the mani-
fold absolute pres-
sure sensor. <Ref.
to FU(H4DOTC)-
40, Manifold Abso-
lute Pressure Sen-
sor.>
Go to step 4. Replace the elec-
tronic throttle con-
trol. <Ref. to
FU(H4DOTC)-14,
Throttle Body.>
Replace the mani- Replace the elec-
fold absolute pres- tronic throttle con-
sure sensor. <Ref. trol. <Ref. to
to FU(H4DOTC)- FU(H4DOTC)-14,
40, Manifold Abso- Throttle Body.>
lute Pressure Sen-
sor.>