Subaru 2009 IMPREZA, Service Manual

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GD(H4SO)-95
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
During deceleration fuel cut from 53 km/h (approx. 33 MPH) or more, perform diagnosis once.
Be careful of vehicle speed and engine speed. (Diagnosis will not be completed if the vehicle speed and en-
gine speed conditions become out of specification due to deceleration.)
5. DIAGNOSTIC METHOD
Measure the pressure values when the enable conditions are established, and perform diagnosis by calcu-
lating those results.
1. Label the intake manifold pressure value as PMOF1, which is observed when enable conditions are es-
tablished, and set the EGR target step to 50 steps (nearly full open).
2. Label the intake manifold pressure value as PMON, which is observed after one second has passed since
EGR target step was set to 50 steps (when the enable conditions were established), and set the EGR target
step to 0.
3. Label the intake manifold pressure as PMOF2, which is observed after one second has passed since EGR
target step was set to 0 (after two seconds have passed since the enable conditions were established).
Secondary Parameters Enable Condition
Elapsed time after starting the engine
t
40 s
Engine coolant temperature
t
75 °C (167 °F)
Engine speed 1200 rpm — 2950 rpm
Intake manifold pressure (absolute pressure) < 44 kPa (330 mmHg, 13 inHg)
Ambient air temperature
t
5 °C (41 °F)
Throttle position < 0.25 °
Battery voltage
t
10.9 V
Barometric pressure
t
75 kPa (563 mmHg, 22.2 inHg)
Vehicle speed
t
58 km/h (36 MPH)
Fuel shut-off function In operation
Neutral switch OFF
After neutral switch ON/OFF change
t
Value from Map
No load change (A/C, power steering, lighting,
rear defogger, heater fan and radiator fan)
t
5000 ms
Map
Engine coolant temperature
°C (°F)
–40
(–40)
–30
(–22)
–20
(–4)
–10
(14)
0
(32)
10
(50)
20
(68)
30
(86)
After neutral switch change
msec
0 0 0 0 0 0 0 0
Engine coolant temperature
°C (°F)
40
(104)
50
(122)
60
(140)
70
(158)
80
(176)
90
(194)
100
(212)
110
(230)
After neutral switch change
msec
0 0 0 0 0 0 0 0