Subaru IMPREZA 2002 Service Manual page 491

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
Step
2 CHECK FUEL LEVEL.
3
CHECK STATUS OF CHECK ENGINE MAL-
FUNCTION INDICATOR LAMP (MIL).
1)Clear the memory using Subaru Select Mon-
itor.
<Ref. to EN(S0HC)-43, Clear Memory Mode.>
2)Start the engine, and drive the vehicle more
than 10 minutes.
CHECK CAUSE OF MISFIRE DIAGNOSED.
4
5
CHECK AIR INTAKE SYSTEM.
6 CHECK MISFIRE SYMPTOM.
1)Turn the ignition switch to ON.
2)Read the diagnostic trouble code (DTC).
*Subaru Select Monitor
<Ref. to EN(S0HC)-32, Subaru Select Moni-
tor.>
*OBD-ll general scan tool
For detailed operation procedures, refer to the
OBD-ll General Scan Tool Operation Manual.
NOTE:
Perform diagnosis according to the items listel
below.
(DTC) ON DISPLAY.
7 CHECK DIAGNOSTIC TROUBLE CODE
Check
;the fuel meter indication
igher than the "Lower" level?
j
the MIL coming on or blink-
lg?
Vas the cause of misfire diag-
losed when the engine is run-
ling?
s there a fault in air intake sys-
em?
Ioes the Subaru Select Moni-
or
or OBD-ll general scan tool
ndicate only one DTC?
loes the Subaru Select Moni-
:or or OBD-ll general scan tool
ndicate DTC PO301 and
'0302?
EN(S0HC)-167
Yes
IO
to step 13.
io to step 15.
inish diagnostics
peration, if the
ngine has no
bnormality.
IOTE:
:x. Remove tht
park plug cord
tc.
tepair air intake
ystem.
IOTE:
:heck the follow
l g items:
2aks or air suctior
aused by loose
oi
lislocated nuts
n d bolts?
Are there crack:
ir any disconnec-
ion of hoses?
$0
to step 21.
Are there air
20
to step 22.
No
leplenish fuel so
iel meter indica-
on is higher than
i e "Lower" level.
,iter replenishing
iel, Go to step 13.
io to step 14.
lepair poor con-
3ct.
IOTE:
i
this case, repaii
i e following:
Poor contact in
jnitor connector
Poor contact in
pition coil con-
lector
Poor contact in
Jel injector con-
lector on faulty
:ylinders
Poor contact in
:CM connector
Poor contact in
:oupling connect0
i o to step 16.
;o to step 17.
30 to step 18.