Page 145 of 548

CAUTION
Do
not
allow
water
to
get
inside
the
thermal
vacuum
valve
EC161A
Fig
EC
77
Ch
c
jng
Th
rmal
Vacuum
Valve
3
port
type
Thermal
vacuum
valve
2
port
type
Dismount
thermal
vacuum
valve
from
engine
Note
Before
dismounting
drain
en
gine
c
oolant
from
engine
Apply
vacuum
to
thermal
vacuum
valve
and
check
to
be
sure
that
ther
SPARK
TIMING
CONTflOL
SYSTE
VI
DESCRIPTION
The
spark
timing
control
system
is
designed
to
control
the
distributor
vacuum
advance
under
varying
driving
conditions
so
as
to
reduce
He
and
NOx
emissions
Emission
Control
System
mal
vacuum
valve
opens
or
closes
in
response
to
engine
coolant
tempera
ture
as
specified
Thermal
vacuum
valve
should
open
at
a
temperature
specified
below
com
pleting
the
vacuum
passage
Thermal
vacuum
valve
opening
temperature
40
to
63
c
104
to
1450
Fl
CAUTION
00
not
allow
water
to
get
inside
the
thermal1
acuum
valve
Jl
i
g
J
eC
42
Fig
EC
78
Ch
ckjng
Thermal
Vacuum
Valve
M
T
model
When
the
transmission
is
shifted
into
the
4th
or
5th
gear
the
electric
current
flows
into
the
vacuum
switch
ing
valve
The
vacuum
switching
valve
is
then
actuated
and
close
the
vacuum
passage
As
a
res
li
the
distributor
fully
advances
its
ignition
liming
When
the
transmission
is
shifted
into
any
gear
other
than
4th
and
5th
current
flow
is
interrupted
The
vacu
umswitclting
valve
is
then
deactuated
and
the
vacuum
leak
passage
is
E026
BoP
T
valve
1
DiSCOIUlect
two
vacuum
hoses
on
BY
T
valve
2
Plug
one
of
two
port
of
BY
T
valve
Apply
a
pressure
above
SO
nimH20
1
97
inHP
to
B
P
T
valve
and
orally
suck
back
other
port
of
B
P
T
valve
as
shown
below
to
check
for
leakage
If
a
leak
is
noted
replace
valve
Apply
pressure
above
SO
mmH10
2
inH10
EC311A
Fig
EC
79
Checking
B
P
T
Valve
opened
This
weakens
the
vacuum
signaUransmitted
from
the
carburetor
As
a
result
the
ignition
timing
of
the
distributor
is
slightly
advanced
On
U
s
A
models
except
for
the
FU
model
a
thermal
vacuum
valve
3
port
type
is
added
on
the
vacuum
line
between
the
carburetor
and
dis
tributor
The
vacuum
signal
is
controlled
by
this
thermal
vacuum
valve
in
accord
ance
with
variation
in
engine
cooling
water
temperature
Page 146 of 548

Emission
Control
System
M
T
models
For
U
S
A
models
except
FU
model
Distributor
r
To
B
P
T
valve
HIGH
vacuum
valve
OrifiCO
i
jarburetor
l
Vacuum
switching
valve
Ignition
switch
I
To
air
cleaner
Fuse
8
Top
switch
4th
5th
Others
Battery
8
ON
OFF
Canada
and
FU
models
OM
1orifico
F
JCMburetor
To
air
cleaner
1
V
cuum
switching
valve
To
intake
manifold
FU
models
only
Fuse
G1j
Ignition
switch
Battery
7
EJ
Top
switch
4th
5th
ON
Others
OFF
EC
27
Water
temperature
OC
OF
Below
5
to
18
41
to
64
Between
I
5
to
18
and
50
t063
41
to
64
and
I
122
to
145
I
I
Above
50
to
63
122
to
145
Transmission
ear
position
Top
4th
and
5111
Other
than
Top
Top
4th
and
5th
Other
than
Top
Top
4th
and
5th
Other
than
Top
Non
California
models
only
Thermal
Spark
timing
vacuwn
valve
Fully
advanced
I
Closed
Partially
advanced
Partially
I
advanced
Partially
I
Open
ad
ced
Fully
I
advanced
I
Closed
Partially
advanced
EC162A
Transmission
gear
Vacuwn
Ignition
timing
switching
position
valve
Top
4th
and
5th
Fully
advanced
Closed
Other
than
Top
Partially
advanced
Open
EC371A
Fig
EC
BO
Spork
Timing
Control
Sy
tem
MIT
Page 147 of 548

Emission
Control
System
AfT
models
Spark
timing
control
systems
on
Arc
models
are
divided
into
3
types
On
California
models
a
top
detect
ing
switch
i3
added
on
the
line
pressure
circuit
beside
the
transmission
case
The
vacuum
switching
v
iJve
and
thermal
vacuum
valve
3
port
type
control
the
spark
advance
by
the
engine
cooling
temperature
and
gear
position
On
non
California
models
excpt
AfT
models
Califomle
models
Distributor
To
B
P
T
valve
1
Orifice
i1J
1
ICh
OJ
L
J
To
air
cleaner
Fu
EJ
Top
5witch
D3
R
ON
Others
4
OFF
Battery
Non
californla
models
except
Canada
To
air
cleaner
l
o
o
0
Ig
o
g
00
00
00
r
Vacuum
delay
valve
Thermal
vacuum
valve
Water
temperature
OC
OF
Thennal
vacuum
valve
Oosed
Ignition
timing
Below
5
10
18
41
io
64
Between
5
to
IB
and
50
to
63
411064
and
122
10
145
Above
50
to
63
122
to
145
Fully
advanced
PartiaDy
advanced
Open
Fully
advanced
Oosed
EC2a
Water
temperature
OC
oF
Bdow
51018
41
to
64
Between
5
to
18
and
50
10
63
411064
and
12210145
Above
50
to
63
122
to
145
Distributor
Carburetor
J
l
Canada
the
thermal
vaCUUDl
Vl
lve
3
port
type
and
vacuum
delay
valve
control
the
spark
advance
On
Canada
models
the
vacuum
delay
valve
is
installed
midway
on
the
vacuum
passage
from
the
carburetor
to
the
distributor
Transmission
gear
position
Thermal
vacuum
va1ve
Ignition
timing
R
and
D
3
FuBy
advanced
Other
than
Rnand
D
3
Oosed
Partially
advanced
R
a
gd
D
3
Other
than
R
and
0
3
Partially
advanced
Open
R
aud
D
3
Fully
advanced
Other
than
R
and
m
3
Oosed
Partially
advanced
Canada
models
Vacuum
delay
valve
Distributor
Carburetor
J
l
EC163A
Fig
EC
81
Spark
Timing
Control
Sy
tem
Af1
J
Page 148 of 548

Vacuumswltching
valve
The
vacuum
switching
valve
changes
the
vacuum
passage
by
the
electrical
signa
The
solenoid
installed
in
the
valve
moves
the
needle
valve
and
controls
vacuum
signal
in
order
to
change
the
vacuum
advance
I
c
III
J
IL
jll
J
EC164A
Fig
EC
82
Vacuum
Switching
Valve
Thermal
vacuum
valve
3
port
type
U
S
A
modele
except
FU
model
The
thermal
vacuum
valve
detects
engine
cooling
water
temperature
and
controls
the
vacuum
signal
for
distrib
utor
vacuum
advance
mechanism
This
3
port
type
thermal
vacuum
valve
is
a
2
stage
action
type
That
is
when
the
water
temperature
is
too
low
or
high
the
acuum
signal
is
transmit
ted
to
the
distributor
ffi2
To
air
cleaner
From
B
PT
valve
From
distributor
EC156A
Fig
EC
83
Thermal
Vacuum
Valve
3
port
type
Top
detecting
switch
For
M
T
models
The
top
detecting
switch
for
M
T
models
is
located
on
the
side
face
of
the
transmission
gear
box
A
plunger
of
the
switch
detects
the
position
of
the
striking
rod
and
Emission
Control
System
changes
the
continuity
between
two
lead
wires
EC165A
Fig
EC
84
Top
Detecting
Switch
Top
detecting
switch
For
Celifornla
AfT
model
The
top
detecting
switch
for
Arr
models
is
installed
as
a
plug
for
t
e
governor
feed
line
pressure
take
out
port
for
service
This
switch
detects
the
line
pressure
for
the
band
servo
release
side
and
front
clutch
and
changes
the
continui
ty
between
lead
wires
to
the
switch
body
EC166A
Fig
EC
85
Top
Detecting
Switch
AfT
model
Vacuum
delay
valve
The
vacuum
delay
valve
prevents
a
rapid
vacuum
change
in
the
distributor
vacuum
advance
line
This
valve
is
designed
for
one
way
operation
and
consists
of
a
one
way
umbrella
valve
and
a
sintered
steel
fluidic
restrictor
B
P
T
valve
side
J
l
1
Sintered
metric
disc
2
One
way
unbreUa
valve
EC860
Fig
EC
86
Vacuum
Delay
Value
EC
29
In
line
orifice
Some
orifices
are
installed
in
the
midway
at
the
vacuum
line
The
size
of
the
orifice
is
important
to
control
vacuum
advance
Therefore
pay
attention
not
to
lose
them
and
install
a
proper
part
when
replacing
Orifice
EC167A
Fig
EC
87
In
line
Orifice
REMOVAL
AND
INSTALLATION
f
Vacuum
switching
valve
The
vacuum
switching
valve
is
located
on
the
rear
end
of
the
intake
manifold
I
Disconnect
a
pair
of
lead
wires
from
valve
and
two
rubber
tubes
2
Loosen
two
screws
securing
valve
to
intake
manifold
Vacuum
switching
valve
can
then
be
taken
out
3
Installation
is
in
the
reverse
s
quence
of
removal
EC16BA
Fig
EC
88
Removing
Vacuum
Switching
Valve
Top
detecting
switch
For
M
T
models
The
top
detecting
switch
is
located
on
the
side
face
of
the
transmission
Page 149 of 548

gear
box
I
Disconnect
a
pair
of
lead
wires
2
Unscrew
the
switch
body
itself
The
switch
can
then
be
taken
out
3
Installation
is
in
the
reverse
se
quence
of
removal
dl
Tightening
torque
Top
cietectingswitch
2
0
to
3
0
kll
m
14
to
22
fHbl
@
EC892
Fig
EC
89
Remouing
Top
Detecting
Switch
Top
detecting
switch
For
AfT
models
The
top
detecting
switch
is
installed
on
the
side
face
of
the
gear
box
I
Disconnect
a
lead
wire
for
top
switch
2
Loosen
switch
itself
Switch
can
then
be
taken
out
Note
When
the
switch
is
remo
ed
automatic
transmission
fluid
flows
out
Prepare
some
rugs
to
prevent
the
fluid
rom
flowing
out
EC169A
Fig
EC
90
Remouing
Top
Detecting
Switch
An
models
3
Insta
tion
is
in
the
reverse
se
quence
of
removal
Emission
Control
System
dl
r
ingtorq
Top
detecting
switch
2
0
to
3
0
kll
m
14
to
22
ft
bl
Thermal
vacuum
valve
3
port
type
The
thermal
vacuum
valve
is
instal
led
on
the
rear
end
of
the
engine
cylinder
head
I
Drain
engine
coolant
about
one
liter
lUllS
qt
Ulmp
qt
2
Remove
manifold
nut
securing
heat
shi
eld
plate
r
l
EC170A
Fig
EC
91
Remouing
Hoot
Shield
Pwte
3
Disconnect
3
vacuum
hoses
and
unscrew
valve
itself
Valve
can
then
be
taken
out
4
Install
thermal
vacuum
valve
in
the
reverse
sequence
of
removal
At
this
time
the
valve
should
be
tighten
ed
to
a
tilt
angle
of
300
Note
Be
sure
to
apply
oealer
to
threads
o
the
valve
prior
to
instal
ling
new
valve
t
J
T1g11taning
torqUe
Thermal
cuum
waive
Less
than
2
2
kll
m
16
ft
bl
Manifold
nut
1
5
to
2
0kg
m
11
to
14
ft
bl
From
distributor
From
B
P
T
valve
From
air
cleaner
ECl71A
Fig
EC
92
mtalling
Thermal
Vacuum
Value
3
port
type
Vacl
ul11
delay
valVe
The
vacuum
delay
Valve
is
installed
on
the
midway
o
the
vacuum
tube
between
the
carburetor
and
distributor
vacuum
advance
mechanism
In
installing
the
valve
make
sure
that
the
brown
face
sid
is
connected
to
the
carburetor
side
Carburetor
sid
C
r
i
J
EG
30
Distributor
side
One
way
umbreDa
valve
Sintered
metal
disc
EC277
Fig
EC
93
In
tolling
Vacuum
Deloy
Value
Page 150 of 548

INSPECTION
Entire
system
U
S
A
MIT
models
except
FU
mo
el
1
Ensure
that
wiring
connectors
are
tight
in
pla
ce
2
Ensure
that
vacuum
hoses
are
properly
cof
1o
c
ed
to
their
positions
3
Ensure
that
distributor
vacuum
controller
properly
functions
4
Set
timing
light
and
start
engine
S
While
engine
cooling
water
tem
pefature
is
below
SOOC
I220F
check
function
of
system
as
follows
WARNING
To
protect
against
accidental
for
ward
surge
engage
parking
brake
firmly
while
above
check
is
being
made
I
Run
engine
and
keep
it
at
ap
proximately
1
600
rpm
2
Disengage
clutch
Shift
gears
in
top
3rd
then
neutral
positions
Read
spark
timing
in
respective
shift
posi
tions
The
system
is
properly
functioning
if
spark
timir
g
does
not
change
If
t
changes
check
thefmal
vacuum
valve
3
port
type
Note
Ensure
that
thermal
vacuum
wIve
is
closed
when
cooling
water
i
below
5
to
lSoC
41
to
640F
or
above
SO
to
630C
122
to
14S0F
I
6
After
the
engine
has
been
warmed
up
sufficiently
check
the
function
of
the
system
again
in
the
I
Same
manner
The
system
is
properly
functioning
if
spark
iimin
advances
in
top
posi
tion
If
not
check
thefmal
vacuum
valve
control
circuit
or
vaeu
um
switching
valve
Entire
system
FU
model
and
Canada
MIl
models
I
Ensure
that
wiri
lg
connectors
are
tight
in
place
Emission
Control
System
2
Ensure
that
vacuum
hoses
are
properly
connected
to
their
positions
3
Ensure
that
distributor
vacuum
controller
properly
fu
ctions
4
Set
timing
light
WARNING
To
protect
against
accidental
for
ward
surge
engage
parking
brake
firmly
while
above
check
is
being
made
5
Run
engine
and
keep
it
at
ap
proximately
1
600
1
m
6
Disengage
clutch
Shift
gears
in
4th
5th
ihen
neutral
positions
Read
spark
timing
in
respective
shift
posi
tions
The
system
is
properly
functioning
if
spark
timing
advances
in
top
gear
position
If
spark
timing
does
not
vary
at
all
in
tests
des
rilied
in
step
6
above
check
control
circuit
or
vacuum
switching
valve
Entire
system
California
AIT
models
I
Ensure
th
t
wiring
connectors
are
tight
in
place
2
Ensure
that
vacuum
hoses
are
properly
coIDwcted
to
thejr
positions
3
Ensure
that
distributor
vacuum
controller
function
s
properly
4
Set
timing
light
and
staft
engine
S
While
engine
cooling
water
tem
perature
is
below
SOOC
1220F
check
the
function
of
the
system
as
follows
WARNING
To
protect
againSt
accidental
for
ward
surge
engage
parking
brake
firmly
while
above
check
is
being
made
I
Run
engine
and
keep
it
at
ap
proximately
1
600
rpm
at
P
range
2
Make
a
short
circuit
between
the
specified
two
terminals
at
function
te
t
connector
EC31
The
entire
system
except
for
the
top
switch
is
properly
functioning
if
spark
timing
does
not
change
If
it
changes
check
the
thermal
vacuum
valve
3
pori
type
CAUTION
Pay
attention
not
to
make
a
short
circuit
between
other
terminals
than
the
specified
terminals
or
electrical
system
of
car
will
get
damaged
4
EC328A
Fig
EC
94
Making
Short
Circuit
6
After
ihe
engine
has
been
warmed
up
sufficiently
check
the
function
of
the
system
again
in
the
same
manner
The
system
except
for
the
top
switch
is
properly
fU
lctioning
if
spark
timing
is
approximately
greater
than
that
without
a
short
circuit
If
not
check
the
thermal
vacuum
valve
control
circuit
or
vacuum
switch
ing
valve
7
As
the
final
step
of
checking
entire
system
top
switch
should
be
checked
as
follows
1
Start
engine
and
keep
at
idling
speed
2
Disconnect
lead
wires
from
vacu
um
switching
valve
at
connetors
CAUTION
Never
forget
this
operation
otherwise
the
circuit
tester
will
get
damaged
Page 151 of 548

EC173A
Fig
EC
95
Disconnecting
Vacuum
Switching
Valve
Connector
3
Apply
parking
brake
and
keep
brake
pedal
fully
depressed
4
Check
continuity
between
two
specified
terminals
ai
function
test
connector
with
gearshift
lever
in
R
or
N
position
The
top
detecting
switch
is
func
tioning
properly
if
the
continuity
is
as
following
table
If
not
replace
the
switch
N
position
No
R
position
Yes
Note
At
idling
CAUTION
Never
race
the
engine
or
car
will
creep
r
q
EC329A
Fig
EC
96
Checking
Top
Detecting
Switch
Arr
model
Emission
Control
System
Entire
system
Non
California
AfT
models
except
Canada
1
Ensure
that
vacuum
hoses
are
properly
connected
to
their
positions
And
confirm
that
gearshift
lever
is
in
P
position
2
Disconnect
vacuum
hose
atdis
tributor
vacuum
controller
3
While
engine
cooling
wat
r
is
be
low
SOoC
1220F
race
engine
and
check
vacuum
for
distributor
If
vacu
um
is
felt
check
thermal
vacuum
valve
3
port
type
4
After
engine
is
sufficiently
warmed
up
repeat
the
above
opera
tion
In
this
case
vacuum
should
be
felt
If
not
check
thermal
vacuum
valve
Vacuu
m
switching
valve
If
spark
timing
does
not
vary
at
all
in
checking
entire
system
check
vacu
um
switching
valve
i
follows
I
Warm
up
engine
sufficiently
2
Disconnect
vacuum
switching
valve
lead
wires
3
Set
timing
light
and
keep
engine
speed
at
approximately
1
600
rpm
On
AfT
models
geaishiftlever
should
be
in
N
or
P
4
Apply
l2V
battery
voltage
to
one
of
two
lead
wires
from
vacuum
switching
valve
Then
connect
the
other
lead
wire
to
ground
At
this
time
spark
timing
should
change
appioximately
by
50
If
it
does
not
replace
vacuum
switching
valve
EC175A
Fig
EC
97
Checking
Vacuum
Switching
Valv
Thermal
vacuum
valve
3
port
type
U
s
A
models
except
FU
model
Remove
thermal
vacuum
valve
from
engine
Inhale
air
from
port
of
spark
EC32
timing
amttol
systetn
andcheck
to
sure
that
thermal
vacuum
valve
opens
or
closes
in
response
to
its
tempera
ture
Thermal
vacuum
walye
closing
temperature
Above
50
to
63
c
122
to
1450
F
Below
5
to
1SoC
41
to
64
Fl
J
EC161A
Fig
EC
98
Checking
Thermal
Vacuum
Valv
CAUTION
Do
not
allow
water
to
get
inside
the
thenna
vacuum
valve
Top
detecting
switch
M
T
models
To
check
top
detecting
switch
for
proper
ON
OFF
operation
contact
leads
of
an
ohmmeter
with
swiich
lead
wires
and
shift
transmiosion
from
TOP
to
other
forward
gear
and
vice
versa
If
switch
does
not
operate
prop
erly
replace
Continuity
of
top
detecting
switch
should
be
a
follows
Other
than
4th
and
5th
No
4th
and
5th
Yes
Note
In
checking
continuity
oCthe
switch
keep
the
ignition
switch
OFF
Otherwise
the
circuit
tester
will
get
damaged
Page 152 of 548

e
In
o
L
1
Ignition
switch
2
Vacuum
switching
v3
lve
3
Top
detecting
switch
4
Function
check
connector
EC330A
i
Fig
EC
99
Checking
Top
Detecting
l
Switch
Vacuum
dela
valve
Remove
vacUum
delay
valve
2
Blow
air
from
th
port
of
the
distributor
side
The
vacuum
delay
valve
is
in
go
ij
condition
if
the
air
flows
through
the
valve
3
Try
again
from
the
opposit
side
of
the
valve
Th
valve
is
in
goo
condition
if
th
a
flow
resistance
is
greater
than
the
step
2
abov
Distributor
side
Carburetor
side
Distribu
tor
side
Carburetor
side
EC346
Fig
EC
100
Checking
Vocuum
Dewy
Valve
Emission
Control
Syst
m
4
If
the
condition
of
spark
delay
valve
is
questionable
dip
port
into
a
cup
filled
with
water
Blow
air
from
brown
face
side
Small
air
bubbles
should
appear
CAUTION
Be
c
areful
to
avoid
entry
of
oil
or
dirt
into
valve
7
E
C279
Fig
EC
101
Checking
Vacuum
D
lDy
Valve
CATALYTIC
CONVERTER
California
dels
DESCRIPTION
1
The
catalytic
converter
accelerates
the
chemical
reaction
of
hydrocarbons
CD
0
He
and
carbon
monoxide
O
in
the
exhaust
gas
and
changes
them
into
non
harmful
carbon
dioxide
C02
and
water
H20
This
chemical
reac
tiOD
process
requires
the
proper
a
mount
of
air
which
is
supplied
by
the
air
pump
Refer
to
the
item
AJ
S
This
air
is
called
secondary
air
The
Catalytic
converter
is
mounted
0
the
models
destinbd
for
California
OPERATION
Exhaust
gas
emitted
from
the
en
gine
contains
some
harmful
substances
due
to
incomplete
combustion
in
the
combustion
chamber
The
air
injection
stem
i
designed
to
reduce
the
con
tent
of
such
substances
in
the
exhaust
gas
In
this
system
the
secondary
air
is
led
from
the
ch
ck
valve
and
injected
in
o
the
exhaust
manifold
With
this
injection
of
the
secondary
air
hydro
carbons
He
and
carbon
monoxide
CO
in
the
exhaust
gas
are
gradually
oxidized
with
oxygen
02
in
the
secondary
air
and
converted
into
nOD
harmful
carbon
dioxide
C02
and
water
HP
The
catalytic
converter
further
cleans
engine
exhaust
gas
Through
catalytic
action
it
changes
residual
hydrocarbons
and
carbon
monoxide
contained
in
exhaust
gas
into
carbon
dioxide
and
water
before
exhaust
gas
is
discharged
to
the
atmosphere
0
Secondary
air
Carbon
monoxide
hydrocarbon
Carbon
dioxide
gas
Nater
EC
i
A
I
Front
tube
2
Catalytic
converter
3
Center
tube
4
Main
murner
EC
33
EC215
Fig
EC
I02
Function
of
Catalytic
Converter