1996 SUBARU LEGACY Pcv valve

ON-BOARD
DIAGNOSTICS
II
SYSTEM
[Tiq2]
2-

1
.
General

1~
Engine
control
module
(ECM)
~
Radiator
fan

~2
Ignition
coil~s
Radiator
fan
relay

~3
Ignitqr
~s
Pressure
sources
switching
solenoid
valve

~4
Crankshaft
position
sensor
~
Knock
sensor

~5
Camshaft
position
sensor
~
Back-pressure
transducer

Throttle
position
sensor
~s
Front
oxygen
sensor

~7
duel
injectors
~o
Rear
oxygen
sensor
(Except
California
model)

~8
Pressure
regulator
~
Pressure
sensor

Engine
coolant
temperature
sensor
~z
A/C
compressor

~o
Mass
air
flow
sensor
~
Inhibitor
switch

Idle
air
control
solenoid
valve
~
CHECK
ENGINE
malfunction
indicator
lamp
(MIL)

~z
Purge
control
solenoid
valve
~
Tachometer

0
Fuel
pump
~s
A/C
relay

0
PCV
valve
~
A/C
control
module

~s
Air
cleaner
~eIgnition
switch

Canister
~
Transmission
control
module
(TCM)

~
Main
relay
~o
Vehicle
speed
sensor
2

~a
Fuel
pump
relay
~
Data
link
connector
(For
Subaru
select
monitor)

~s
Fuel
filter
@
Data
link
connector
(For
Subaru
select
monitor
and

~o
Front
catalytic
converter
OBD-II
general
scan
tool)

Rear
catalytic
converter
@
Two
way
valve

~2
MGR
valve
~a
Rear
oxygen
sensor
(California
model
only)

EGR
control
solenoid
valve
~
Filter

3

ON-BOARD
DIAGNOSTICS
11
SYSTEM
[T10A0]
2-7

10
.
Diagnostics
Chart
with
Trouble
Code

DTC

No
.

Abbreviation

(Subaru
select
monitor)Item
Page

P0500
VSP
Vehicle
speed
sensor
malfunction
'1

P0505
ISC
Idle
control
system
malfunction
`1

P0506
ISC
-
L
Idle
control
system
RPM
lower
than
expected
'1

P0507
ISC
-
H
Idle
control
system
RPM
higher
than
expected
'1

P0600
-
Serial
communication
link
malfunction
`1

P0601
RAM
Internal
control
module
memory
check
sum
error
'1

P0703
ATBRK
Brake
switch
input
malfunction
'1

P0705
ATRNG
Transmissionrange
sensor
circuit
malfunction
`1

P0710
ATF
Transmission
fluid
temperature
sensor
circuit
malfunction
'1

P0720
ATVSP
Output
speed
sensor
(vehicle
speed
sensor
1)
circuit
malfunction
'1

P0725
ATNE
Engine
speed
input
circuit
malfunction
'1

P0731
ATGR1
Gear
1
incorrect
ratio

P0732
ATGR2
Gear
2
incorrect
ratio
"
1
P0733
ATGR3
Gear
3
incorrect
ratio

P0734
ATGR4
Gear
4
incorrect
ratio

P0740
ATLU
-
F
Torque
converter
clutch
system
malfunction
1

P0743
ATLU
Torque
converter
clutch
system
electrical
*1

P0748
ATPL
Pressure
control
solenoid
electrical
'1

P0753
ATSFTi
Shift
solenoid
A
electrical
`1

P0758
ATSFT2
Shift
solenoid
B
electrical
'1

P0760
ATOVR
-
F
Shift
solenoid
C
malfunction
'1

P0763
ATOVR
Shift
solenoid
C
electrical
'1

P1100
ST-SW
Starter
switch
circuit
malfunction
'1

P1101
N/P
-
SW
Neutral
position
switch
circuit
malfunction
[MT
vehicles]
'1

P1101
N/P
-
SW
Neutral
position
switch
circuit
malfunction
[AT
vehicles]
1

P1102
BR
Pressure
sources
switching
solenoid
valve
circuit
malfunction
'1

P1103
TRQ
Engine
torque
control
signal
circuit
malfunction
`1

P1400
PCVSOL
Fueltank
pressure
control
solenoid
valve
circuit
malfunction
38

P1401
PCV
-
FFueltank
pressure
control
system
function
problem
44

P1402
FIVL
Fuel
level
sensor
circuit
malfunction
46

P1500
FAN
-
1
Radiator
fan
relay
1
circuit
malfunction
'1

P1502
FAN
-
F
Radiator
fan
function
problem
'1

P1700
ATTH
Throttle
position
sensor
circuit
malfunction
for
automatic
transmission
'1

P1701
ATCRS
Cruise
control
set
signal
circuit
malfunction
for
automatic
transmission
'1

P1702
ATDIAG
Automatic
transmission
diagnosis
inputsignal
circuit
malfunction
'1

P0461'2
EXERR22
Fuel
level
sensor
circuit
range/performance
problem
56

"1
:
<
Ref
.
to
2-7
[T11A0]
.*4
>

'2
:
Only
OBD-II
general
scan
tool
displays
DTC
.

2_7
[T1oBUO1
ON-BOARD
DIAGNOSTICS
II
SYSTEM

10
.
Diagnostics
Chart
with
Trouble
Code

OBD
(FBI)

P1400


H2M
1406

BU
:
DTC
P1400

-
FUEL
TANK
PRESSURE
CONTROL

SOLENOID
VALVE
CIRCUIT
MALFUNCTION

(PCVSOL)
-

DTC
DETECTING
CONDITION
:

Two
consecutive
trips
with
fault

10131
.11
Check
output
signal
from
ECM
.

I

10BU2
Check
harness
between
fuel
tank

pressure
control
solenoid
valve
and
ECM

connector
.

1081
.13

Check
harness
between
fuel
tank

pressure
control
solenoid
valve
and
ECM

connector
.

10BU4Check
fuel
tank
pressure
control

solenoid
valve
.

10BU5Checkpower
supply
to
fuel
tank

pressure
control
solenoid
valve
.

CAUTION
:

After
repair
or
replacement
of
faultyparts,
conduct

CLEAR
MEMORY
and
INSPECTION
MODES
.

<
Ref
.
to
2-7
[T3D0]
and
[T3E0]
.*2
and
*4
>

38

2-7
[T1
oBVO1
ON-BOARD
DIAGNOSTICS
II
SYSTEM

10
.
Diagnostics
Chart
with
Trouble
Code

OBD
(FBI)

P1401

H21
M1410

BV
:
DTC
P1401

-
FUEL
TANK
PRESSURE
CONTROL
SYSTEM

FUNCTION
PROBLEM
(PCV
-
F)
-

DTC
DETECTING
CONDITION
:

Two
consecutive
trips
with
fault

10BV1
Check
fuel
tank
pressure
control

solenoid
valve
.

CAUTION
:

After
repair
or
replacement
of
faulty
parts,
conduct

CLEAR
MEMORY
and
INSPECTION
MODES
.

<
Ref
.
to
2-7
[T3D0]
and
[T3E0]
.*2
and
*4
>

WIRING
DIAGRAM
:

Main
relay
0

0

01F
B47861F45
SBF-2
B84

E
E)E)
ECM

ra

Ti

S
.M
.J
.
891
Rt
R15
R57R68
Fuel
tankpressure
control
solenoid
valve

847
R57R68

10
U
1112
U
131401
16

1
131
1
4041424344
1
2
960
6162
63
64
6
-769
69
70
34
1~,~y(3~
8
.04
687
8
99091929
949
96
6
14j5jti1/LtiJ

B2M1020

44

4. Valve Rocker Assembly
A: REMOVAL
B2M0418A
B2M0382A
1) Disconnect PCV hose and remove rocker cover.
2) Removal of valve rocker assembly
(1) Remove bolts

1through
4in numerical sequence.
CAUTION:
Leave two or three threads of bolt

1engaged to retain
valve rocker assembly.
(2) Equally loosen bolts

5through
8all the way, being
careful that knock pin is not gouged.
B2M0414
(3) Remove valve rocker assembly.
CAUTION:
Locate valve rocker assembly with air vent (on rocker
arm) facing upward or dip it in engine oil after removal.
27
2-3SERVICE PROCEDURE
4. Valve Rocker Assembly

E: INSTALLATION
B2M0418B
Tightening torque: N⋅m (kg-m, ft-lb)
T1: 5±1 (0.5±0.1, 3.6±0.7)
T2: 12±1 (1.2±0.1, 8.7±0.7)
B2M0382B
1) Installation of valve rocker assembly
(1) Temporarily tighten bolts

1through
4equally as
shown in Figure.
CAUTION:
Do not allow valve rocker assembly to gouge knock
pins.
(2) Tighten bolts

5through
8to specified torque.
(3) Tighten bolts

1through
4to specified torque.
2) Install rocker cover and connect PCV hose.
32
2-3SERVICE PROCEDURE
4. Valve Rocker Assembly

TROUBLE
Engine will not start.
Rough idle and engine stall
Low output, hesitation and poor acceleration
Surging
Engine does not return to idle.
Dieseling (Run-on)
After burning in exhaust system
Knocking
Excessive engine oil consumption
Excessive fuel consumption Starter does not turn.
Initial combustion does not occur.
Initial combustion occurs.
Engine stalls after initial combustion.
INTAKE SYSTEM
2111 3Loosened or cracked intake air pipe
3111 3 1Loosened or cracked blow-by hose
31211 2Loosened or cracked vacuum hose
22222Defective intake manifold gasket
22222Defective throttle body gasket
322 2 2Defective PCV valve
222 323Loosened oil filler cap
3312 1Dirty air cleaner element
FUEL LINE
13 322Defective fuel pump and relay
33322Clogged fuel line
222233Lack of or insufficient fuel
BELT
222Defective
222322 22 2Defective timing
FRICTION
3Seizure of crankshaft and connecting rod bearing
3Seized camshaft
3Seized or stuck piston and cylinder
COMPRESSION
333222 23 2Defective hydraulic lash adjuster
333223 3 3Loosened spark plugs or defective gasket
333223 3 3Loosened cylinder head bolts or defective gasket
333223 2 2Improper valve seating
333333 3 13Defective valve stem
222223 3 3Worn or broken valve spring
333233 3 12Worn or stuck piston rings, cylinder and piston
222111 12 2Incorrect valve timing
222222Improper engine oil (low viscosity)
76
2-3DIAGNOSTICS
1. Engine Trouble in General

TROUBLE
Engine will not start.
Rough idle and engine stall
Low output, hesitation and poor acceleration
Surging
Engine does not return to idle.
Dieseling (Run-on)
After burning in exhaust system
Knocking
Excessive engine oil consumption
Excessive fuel consumption Starter does not turn.
Initial combustion does not occur.
Initial combustion occurs.
Engine stalls after initial combustion.
INTAKE SYSTEM
2111 3Loosened or cracked intake air pipe
3111 3 1Loosened or cracked blow-by hose
31211 2Loosened or cracked vacuum hose
22222Defective intake manifold gasket
22222Defective throttle body gasket
322 2 2Defective PCV valve
222 323Loosened oil filler cap
3312 1Dirty air cleaner element
FUEL LINE
13 322Defective fuel pump and relay
33322Clogged fuel line
222233Lack of or insufficient fuel
BELT
222Defective
222322 22 2Defective timing
FRICTION
3Seizure of crankshaft and connecting rod bearing
3Seized camshaft
3Seized or stuck piston and cylinder
COMPRESSION
333222 23 2Defective hydraulic lash adjuster
333223 3 3Loosened spark plugs or defective gasket
333223 3 3Loosened cylinder head bolts or defective gasket
333223 2 2Improper valve seating
333333 3 13Defective valve stem
222223 3 3Worn or broken valve spring
333233 3 12Worn or stuck piston rings, cylinder and piston
222111 12 2Incorrect valve timing
222222Improper engine oil (low viscosity)
76
2-3bDIAGNOSTICS
1. Engine Trouble in General