Subaru IMPREZA 2002 Service Manual page 479

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
~
Step
CHECK FUEL PRESSURE.
After connecting the pressure regulator vac-
uum hose, measure fuel pressure.
Warning:
Before removing the fuel pressure gauge,
release fuel pressure.
NOTE:
.If fuel pressure does not increase, squeeze
fuel return hose 2 to 3 times, then measure
fuel pressure again.
. I f out of specification as measured at this step,
check or replace pressure regulator and pres-
sure regulator vacuum hose.
CHECK ENGINE COOLANT TEMPERATURE
SENSOR.
1)Start the engine and warm-up completely.
2)Read the data of engine coolant temperature
sensor signal using Subaru Select Monitor or
OBD-ll general scan tool.
NOTE:
OSubaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE. <Ref.
to EN(S0HC)-32, Subaru Select Monitor.>
.OBD-ll general scan tool
For detailed operation procedures, refer to the
OBD-ll General Scan Tool Instruction Manual.
CHECK INTAKE MANIFOLD PRESSURE
SENSOR SIGNAL.
1)Start the engine and warm-up engine until
coolant temperature is greater than 60°C
(1 40°F).
2)Place the selector lever in "N" or " P position
3)Turn the A/C switch to OFF.
4)Turn all accessory switches to OFF.
5)Read the data of intake manifold pressure
sensor signal using Subaru Select Monitor or
OBD-II general scan tool.
NOTE:
.Subaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE". <Ref.
to EN(S0HC)-32, Subaru Select Monitor.>
.OBD-II general scan tool
For detailed operation procedures, refer to the
OBD-ll General Scan Tool Instruction Manual.
Specification:
Idling
-
24.0
-
41.3 kPa (180
-
310 mmHg, 7.09
-
12.20 inHg)
73.3
-
106.6 kPa (550
-
800 mmHg,
21.65
-
31.50 inHd
Ignition ON
Check
s fuel pressure between 206
ind 235 kPa (2.1
-
2.4 kgl
:m2, 30
-
34 psi)?
s
temperature between 70°C
158°F) and 100°C (21 2"F)?
s the voltage within the specifi,
:ations?
Yes
i o to
step 5.
; o to step 6.
:ontact with
S(
distributor) ser
ice.
JOTE:
nspection by C
3
required,
:ause probc
:ause is deteric
ion of mult
)arts.
No
3epair the follow-
ng items.
'uel pressure too
)igh
Faulty pres-
sure regulator
Clogged fuel
return line or
bent hose
'uel pressure too
Faulty pres-
sure regulator
Improper fuel
pump discharge
Clogged fuel
supply line
3eplace the
mgine coolant
emperature sen-
ior. <Ref. to
ingine Coolant
remperature Sen-
ior.>
DW
W(SOHC)-27,
3eplace the intake
iir temperature
ind pressure sen-
ior. <Ref. to
ntake Air Temper-
iture and Pres-
iure Sensor.>
W(SOHC)-34,
EN(S0HC)-155