sensor DATSUN PICK-UP 1977 Service Manual

Engine
Tune

up

EC284

When

installing
this
valve

ensure

that
it

properly
oriented
This
valve

should
be

replaced
periodically
Refer

to
Maintenance
Schedule

I

To

distribut0
From

carburetor

Yl
r

EC278
l

Fig
ET
24
Operation
of
spark
delay

value

I

I

Carburetor
side

Distributor
side

rJmlL
lr

EC346

Fig
ET
25
Checking

spark
delay
value
Distributor
side

Brown

lOne
way
umbrella
valve

2
Sintered
metal
disc

Fig
ET
23
Spark
delay
valve

INSPECTION

I
Remove

spark
delay
valve

2
Blow
air

through
port
on

carbure

tor
side
then

through
the

other
port

on
distributor
side

Spark
delay
valve

is
in

good
condition
if
when

finger
is

placed
over

port
on
distrib
side

ajr
flow
resistance
is

greater
than
that

on
the
other

side
See

Figure
ET
25

3
If
a
considerable
air
flow
resist

ance
is
felt
at

port
on
distributor
side

in

step
2

above
and

if
the
condition
of

spark
delay
valve
is

questionable
dip

port
on
carburetor

side
into
a

cup

fIlled
with
water
Blow
air

through
the

other

port
Small
air
bubbles
should

appear

EC279

Fig
ET
26

Checking
spark
delay
ualue

Note
Be

careful
to

avoid

entry
of
oil

or
dirt
into
valve

ET
15
CHECKING

AUTOMATIC

TEMPERATURE

CONTROL
AIR

CLEANER

1
Air
cleener
element

Viscous

paper
type
air
cleaner
ele

ment
does
not

require
any
cleaning

opera
tion

until
it
is

replaced
periodi

cally
Brushing
or

blasting
operation

will

cause

clogging
and
result
in
enrich

ment
of
carburetor
mixture
and

should
never
be
conducted
For
reo

placement
interval
of
air
cleaner
ele

ment
refer

to
Maintenance
Schedule

2
Hot

elr
control
system

In
warm
wealher
it
is
difficult
to

find
ou

t
malfunction
of
hot
air
control

system
In
cold
weather
however

malfunction
of
air
control
valve
d

e
to

disconnection
or
deterioration
of
vacu

um
hose
between
intake
manifold
and

vacuum
motor
and
insufficient
dura

bili

ty
of
air

con
trol
valve
will
cause

insufficient
automatic
control

opera

tion
for
intake
air
and
result
in

engine

disorder

including

I

Stall
or
hesitation
of

engine

opera

tion

2

Increase
in
fuel

consumption

3
Lack
of

power

These

phenomena
reveal
malfunc

tionof
hot
air
control

system
If
these

phenomena
should
occur
check
hot

air
control

system
as
described
in
the

following
before

carrying
ou

t

inspec

tion
of
carburetor

2
1
Vacuum
hoses

Intake
manifold
to
3

way
connec

tor
3

way
connector
to

temperature

sensor
3

way
connector
to
idle
com

pensator
temperature
sensor
to

vacu

um
motor

1

Check
that
vacuum
hoses
are
se

curely
connected
in

correct

position

2
Check
each
hose
for
cracks
or

distortion
hose

clip
for
condition

Note
Vacuum
hose

position
R
R

side
of
Nissan
mark
on
the

top
of

sensor
for

intake
manifold
L
R

side
of
the

mark
is
for
vacuum

rootor

2
2

Vacuum
motor

I
With

engine
stopped
disconnect

fresh
air
duct

Place
a
mirror
at
the

end
of
air

cleaner
inlet

pipe
as
shown
and
check

to
see
if
air

control
valve
is
in

correct

position

EF213

Fig
ET
27

Impecting
lJalv

position

Air
control
valve
is
in
correct

posi

tion
if
its
under
hood
air
inlet
is

open

and
hot
air
inlet
is

closed
Check
air

control
valve

linkage
for
condition

2

Disconnect
vacuum
motor
inlet

vacuum
hose
and
connect
another

hose
to

the
inlet
to

apply
vacuum
to

vacuum
motor
Vacuum
can
be

ap

plied
by
breathing
in

the
hose
end
as

shown

Place
a
mirror
at
the
end
of
air

cleaner
inlet

pipe
and
check
to
see
if

air
control
valve
is
in
correct

position
Engine
Tune

up

EF217

Fig
ET
28

lmpecting
value

position

Correct

pC6ition
of
air

control
valve

is
the

reverse
of

paragraph
I
above
Air

control
valve
is
in
correct

position
if

under
hood
air
inlet
is
closed
and
hot

air

inlet
is

open

3
With
hot
air
inlet
is

open
posi

tion
as
descnbed
in

paragraph
2

above

pinch
vacuum
hose
with

fingers

and
cut
of
air
from
vacuum
hose

In

this
condition
check
that
air

control

valve
maintains
the
condition
de

scribed
in

step
2

for

more
than
30

seconds
and

that
hot
air
inlet
is

open

If

diaphragm
spring
actuates
the

air

control
valve

by
its

spring
force

to

open
under
hood
air

inlet
within
30

seconds

replace
vacuum
motor
as
an

assembly
since
this

may
be
resulted

from
air

leak
at

vacuum
motor
dia

phragm

2
3

Temperature
sensor

Check

temperature
sensor
for
func

tion

by
proceeding
as
follows
Be

sure

to

keep
engine
cold
before

starting

test

1
With

engine
off
check
air

control

valve
for
condition
In
this
case
under

hood
air

inlet
is

open
Use
a
mirror
for

inspection
as
2
2
1

above

2
Start

engine
and

keep
idling

Immediately
after

engine
starting

check
air

control
valve
for
correct

position
as
described
above
In
this

case
correct

position
of
air
control

valve
is
the
reverse
of
2
2
1
under

hood
air

inlet
is

closed
and
hot
air

inlet
is

open

ET

16
3

Check
that
air
control
valve

grad

ually

opens
to
under
hood
air
inlet

side
as

engine
warms

up
When
en

vironmental

temperature
around
tern

perature
sensor
is
low

spend
more

time

for

engine
warming
up
operation

to

facilitate
smooth

opera
tion
of
air

con
trol
valve

If
the
above

test
reveals

any
prob

lem
in
the

operation
of
air
control

valve

carry
out
the

following
test

4

Remove
air
cleaner
cover
Set

temperature
sensing
element

of
ther

mistor
or
thermometer
to

a
position

where

tempera
ture
around
sensor
can

be
measured
In
this
case
fix

wiring
of

thermistor
or
thermometer
on
the
bot

tom
surface
of
air

cleaner
with
adhe

sive

tape
in

such
a
manner
that

the
set

position
of

temperature
sensing
ele

ment
will
not

be
affected

by
airflow

Then
install
air
cleaner
cover

EF221

Fig
ET
29
Checking
temperotur
e

ensor

5

Carry
out
test
as
described
in

steps
I
2

and
3
above
When
air

control
valve

begins
to

open
to
under

hood
air
inlet
side
severa
minutes

after

engine

starting
read
the
indica

tion
of
thermistor
or

thermometer
If

reading
falls
within
the

working
tern

perature
range
of

temperature
sensor

the
sensor
is

normaL
If

reading
ex

ceeds
the

range

replace
the
sensor

with
new
one

Note
Before

replacing
temperature

sensor
check
idle

compensator
as

described
in
Section
EF

page
EF
8

Condition

IMPROPER
ENGINE

IDLING

Fuel

system
out
of

order

Low

compression

Others

High
engine
idle

speed
Engine
Tune

up

Probable
cause

Clogged
or

damaged
carburetor

jets

Incorrect
idle

adjustment

Clogged
air
cleaner
filter

Damaged
manifold

gaskets
or
carburetor

insulator

Improper
float
level

adjustment

Loose
air

hoses
or
air

fuel
mixture
hoses
of

carburetor

Malfunctioning
carburetor
choke

Malfunctioning
anti

backfire
valve

Malfunctioning
automatic

temperature
con

trol
air

cleaner

Inoperative
idle

compensator

Carbon
canister

purge
line
hose

damaged
or

disconnected

Stick
E

F
E
valve
shaft

Incorrect
valve
clearance

Extremely
low
revolution

Faulty
malfunction
of
the

ignition
system

spark
plug

high
tension
cable
breaker

point
ignition
coil
etc

Incorrect
basic

ignition
timing

Malfunction
of
choke
valve
or

linkage

Malfunction
of
vacuum
motor
sensor
or

hoses
of
air
cleaner

Incorrect
idle

adjustment

Clogged
air
cleaner
fdter

Malfunction
of
idle

compensator
of

air

cleaner

Malfunction
of
E
G
R
control
valve

Loose
manifold
and

cylinder
head
bolts

Dragged
accelerator

linkage

Incorrect
idle

adjustment

Malfunction
of
B
CDD

system

Malfunction
of

speed
switch
and
harness

ET
29
Corrective
action

Clean
or

replace

Adjust

Replace
element

Replace
gasket
or
insulator

Adjust

Check
for
loose
connections

Check
and

adjust

Check
for
loose
connection
of
vacuum
hose

Check
A

r
C
air
cleaner

Check
for
connection
of
idle

compensator

hose

or
replace
idle

compen
tor

Connect
or

replace

Repair

Previously
mentioned

Adjust

Adjust

Replace

Adjust

Adjust

Check
for
loose
hoses

Replace
system
com

ponents
if
necessary

Adjust
idle

speed

Replace
air
cleaner
fdter

Replace

Clean
or

replace

Retighten
bolts

Check
and

correct
accelerator

linkage

Adjust
idle

speed

Check
for
loose

vacuum
hose
and
harness

connections

Adjust
or

replace
if

necessary

Check
for
loose
connections

Repair
or

replace
if

necessary

Engine
Fuel

AUTOMATIC

TEMPERATURE
CONTROL
A
T

C

AIR

CLEANER

DESCRIPTION

OPERATION

A
T
C

AIR
CLEANER

HOT
AIR

OPERATION

A
T
C
AIR
CLEANER
COLD
AIR

OPERATION

A
T
C
AIR
CLEANER
COLD
AND

HOT

AIR
OPERATION

TEMPERATURE
SENSOR

DESCRIPTION

The
air

cleaner
removes
dust
and

dirt
from
the

air
before

it
enters
the

carburetor
and

engine
It
also

muffles

noise

resulting
from
the
intake

of
air

into
the

engine

The
air

cleaner

especially
designed

for

improved
exhaust
emission

control

is
referred
to

as
Automatic

Tempera

ture
Control

Air
Cleaner
In
order
to

reduce
HC
emission

when
the

under

hood

temperature
is

below
300C

860F
the

automatic

temperature

control

system
maintains
the

tempera

ture
of
air
to

be
sucked
in
the

carbure

tor
at
30

to
540C
86
to
1290F

thereby
enabling
lean

setting
for

carburetor

calibration
n

addition
to

this
the

automatic

temperature
con

twl

system
is

effective
to

improve

warm

up
characteristics
of
the

engine
CONTENTS

EF
2

EF
3
VACUUM

MOTOR
AND
AIR

CONTROL

VALVE

REMOVAL
AND

INSTALLATION

TEMPERATURE

SENSOR

VACUUM

MOTOR

FRESH

AIR

DUCT

AIR

CLEANER

INSPECTION

1
AIR

CLEANER
ELEMENT

2

HOT
AIR

CONTROL

SYSTEM
EF
3

EF
4

EF
4

EF
5

and
to

remove

carburetor

icing

The

A
T
C
air

cleaner

system
con

sists

of
the

following
devices

1
Air
cleaner

element

The
air

cleaner

element

employed
is

a

viscous

paper
type
It

requires
only

periodical
replacment
and
should
not

be

cleaned

2

Automatic

temperature
control

air

cleaner

In
the
A

T
C
air

cleaner
the
air

control
valve
is
actuated

by
intake

manifold

vacuum
to
control

the
intake

air
flow

circuit
The

temperature
sen

sor
detects
the

temperature
inside
the

air

cleaner
and

opens
or
closes
the

vacuum

passage

3

Hot
air
duct

The
hot
air
duct
is

mounted
on
the

exhaust
manifold
The
air
warmed

up

EF
2
EF
5

EF

5

EF

5

EF

5

EF
5

EF
6

EF
6

EF

6

EF

6

between
the

exhaust
manifold
and
hot

air
duct

is
led
to
the
air
cleaner

through
the

hose

4
Blow

by

gas
filter

The
blow

by

gas
nIter
removes
dirt

and
oil
from
the

blow

by
gas
sucked

in

the
air
cleaner
from
the

engine
rocker

cover

5

Fresh
air

duct

Except
for

Canada

The
fresh
air

duct
leads
the

outside

fresh
air

directly
to

the
air
cleaner

6
Idle

compensator

See

paragraph
Idle

Compensator

Page
EF
7

7

Altitude

compensator
California

models

See

paragraph
Altitude

Compensa

tor

Page
EF
20

Engine
Fuel

@

1

Fresh
air
duct

Except
for
Canada

2

Air
inlet

pipe

3
Vacuum
motor

assembly

4
Air
control
valve

5
Hot
air

pipe

6
Idle

compensator

7
Blow

by

gas
fiI
teT

8

Temperature
sensor
assembly

9
Altitude

compensator

California
models

EF713

Fig
EF
1
Automatic

temperature
control
air
cleaner

OPERATION

The
automatic

temperature
control

system
of
the
air

cleaner
is

controlled

by
the

inlet
air

temperature
and
the
load
condition
of
the

engine
The
inlet

air

temperature
is
detected

by
the

sensor
and
the
vacuum
motor
is
actu
ated

by
the

engine
intake
vacuum

Under
hood
air
Sensor
vacuum
at
Air

control
valve

Sensor

operation

temperature
vacuum
motor
side

operation

Below
60

mmHg

Open
cold
air

Below
300C
2
36

inHg

860

F
Close

Above
210
mmHg

Close
hot
air

8
27

inHg

30

to

540C
Half

open

Open

86
to
1290

F
cold
air
hot
air

Above
55
oC

Open
cold
air

Open

1310F

A
T
C
AIR
CLEANER
HOT

AIR

OPERATION

When
the
under
hood

air

tempera

ture
is
low
the

sensor
air
bleed
valve

remains
in
the

closed

position
and

establishes
vacuum

passage
between
the
intake

manifold
and

vacuum

motor
With
this
condition
the
vacu

urn

at
the
intake
manifold
side
actu

ates
the
air

control
valve
attached
to
the

vacuum
motor

diaphragm
to
intro

duce
hot
air
into
the
air
cleaner

through
the
hot
air

duct
on
the

ex

haust
manifold

EF
3

Underhood
air

I

@
Dr

Underhood
air

I
Engine
Fuel

f
f
l

l

ID
s

6

Cif

Ittl
ID
Air
inlet

pipe

Air
con
trol
valve

Hot
air

pipe

Diaphragm

Vacuum
hose

Diaphragm
spring

Air
bleed
valve

closed

Temperature
sensor

assembly
Holair

EF114

Fig
EF
2
Hota
r

delivery
mode

During
cold

engine
operation

7

To
manifold
Small

vacuum

1
Air
inlet

pipe

2
Air
con
trol

valw

3
Hot
air

pipe

4

Diaphnp

S
V
leuum
hoses

6

Diaphragm
prinl

7
Air

bleed
valve

closed

II

Temperature
senSOr

assembly

EF20S

Fig
EF
3
Cold
air

delivery
mode

During
cold

engine
operation

f
1

J
liP

omanifold
2

@
Air
inlet

pipe

Air

control
valve

Hot
air

pipe

Diaphragm

Vacuum
hoses

Diaphragm
spring

Air
bleed
valve

fully
open

8

Temperature
sensor

assembly

EF715

Fig
EF
4
Cold
air

delivery
mode

During
hot

engine
operation

ID

@
f

fjr

R
lfl
ow

2

underh
r
5

rv

Itti
ID

Hot
air
Air
inlet

pipe

Air
control
valve

Hot
air

pipe

Diaphragm

Vacuum
hose

Diaphragm
spring

Air
bleed
valve

partially
opened

8

Temperature
sensor

assembly

EF716

Fig
EF
5

Regulating
air

delivery
mode

EF
4
A
T
C
AIR
CLEANER

COLD
AIR
OPERATION

I

When
under
hood
air

temperature

is
low

The
sensor
air
bleed

valve
remains

in

the
closed

position
and
vacuum

passage
is

established
between
the
in

take
manifold
and

the
vacuum
motor

and
the
intake
manifold

vacuum
is

applied
to
the

vacuum
motor
dia

phragm
When
the

vacuum
is

small
or

when
the

engine
is

operating
under

eavy

1004
the
air

control
valve

opens

widely

irrespective
of
the

temperature

around
the

sensor
to
introduce
the

under
hood
air

cold
air

for
increased

power
of
the

engine

2

When
under

hood
air

temperature

is

high

The

sensor
air

bleed
valve

opens

fully
to
shut
off

the
vacuum

passage

between

the
intake
manifold
and
the

vacuum
motor
Due
to
the
force
of
the

vacuum
motor

diaphragm
spring
the

air

control
valve

closes
the
hot
air

pipe

of
the
air

cleaner
and

introduces
the

under

hood
air

cold
air

A
T
C
AIR
CLEANER

COLD

AND
HOT

AIR
OPERATION

When
the
sensor
air

bleed
valve
is

partially
opened
opening
of

the
air

control
valve
varies

with
the
vacuum

of
the

intake
manifold
With
the
air

control
valve
half
open

the
cold
air

and
hot
air
are
sucked

together
and

mixed
for

controlling
of
the
air

tem

perature
of
the
air

to
be
introduced
to

the
air

cleaner

TEMPERATURE
SENSOR

The

temperature
sensor
is

attached

to
the

inside
of
the
air

cleaner
The

bimetal
built
in

the
sensor
detects
the

under

hood
air

temperature
and

opens

or

closes
the
vacuum

passage
in
the

sensor

The
construction
of
the

tempera

ture
sensor
is
shown
in

the

following

CD
V
00
@

I

I

@
j
I

I

1
Protector
cover

Screw

Adjusting
frame

Air

temperature
bi

metal

Rivet

Valve
seat
frame

Lower
frame

Air
bleed
valve

Gasket

Fig
EF

6

Temperature
senior
EF206

VACUUM
MOTOR
AND

AIR
CONTROL
VALVE

The
vacuum

pressure
which
varies

with

opening
of
the
carburetor
throt

tle
acts

upon
the
vacuum
motor

dia

phragm
The
valve

shaft
attached
to

the

diaphragm
is
then
moved

up
or

down
in

response
to
the
vacuum
on

the

diaphragm
This
movement
of

the

valve
shaft

actuates
the
air
control

valve
to

control
the

temperature
of
the

air
to

be
introduced
into

the
air

cleaner

pr
to

I

1
Valve

spring

00
2

Diaphragm

@
3
Retainer

E
F

207
4
Valve
shaft

Fig
EF
7
Vacuum
motor

REMOVAL
AND

INSTALLATION

TEMPERATURE
SENSOR

Removal

Using

pliers
flatten

clip
con
Engine
Fuel

neeting
vacuum
hose
to
sensor
vacuum

tube

I

Pipe

2
Calch

3
Fixed
with

adhesive

4
Hose

5

Tab

6

Clip

7
Gasket

EC019

Fig
EF
B
Removal

of
semor

2

Disconnect
hose
from

sensor

3

Take
off

clip
from
sensor
vacuum

tube
and
dismount
sensor

body
from

air
cleaner

Note
The

gasket
between

sensor
and

air
cleaner
is
bonded
to
the
air

cleaner
side
and
should
not
be

removed

Inatallatlon

Mount
sensor
on
the

specified

position

For

mounting
position
of
sensor

see
the

following

EF717

Fig
EF
9

lalling
se
or
2
Insert

clip
into
vacuum
tube

of

sensor
After

installing
each
vacuum

hose
secure
hose
with
the

clip

Note
Be
sure
to
install
vacuum
hose

correctly
Correct

position
is
R

H

side
to
Nissan
mark
at
the

top

face
of

sensor
for
intake
manifold

L
H
side
for
vacuum
motor

VACUUM
MOTOR

1

Remove
screws

securing
vacuum

motor
to
air
cleaner

2
Disconnect
valve
shaft
attached

to

vacuum
motor

diapluagm
from
air

control
valve

and
remove
cacuum

motor

assembly
from
air

cleaner

3
To
install
reverse
the
removal

procedure

FRESH
AIR
DUCT

I
Disconnect
fresh
air
duct
at
air

cleaner

2

Fresh
air

duct
is

provided
with

projections
on
its
air
inlet
side
end

Hold
fresh
air
duct
with
a
hand
and

carefully

pull
out
from
radiator
core

support
while

turning
it
in
either

direction

3
To

install
reverse
the
removal

procedure
Be
sure
to

insert

projec

lions
of
fresh
air
duct

securely
into

mounting
hole
in

radiator
core

sup

port

EF518

EF
5
Fresh
air
duct

Air
cleaner

Duct

mounting
hole

Radiator

Radiator
core

support

Fig
EF

I0
Removal

of
fresh
air
duct

r

AIR
CLEANER

1
Loosen

bolts

securing
air
cleaner

to
air
cleaner
bracket

2
Loosen
air

cleaner
lock
bolt
and

remove
air

cleaner
from
carburetor

Disconnect
the

following
hoses
when

dismounting
air

cleaner

Under
hood
air
inlet

hose

Hot
air
inlet

hose

Vacuum

hose
Sensor
to
intake

manifold

Vacuum
hose
Sensor
to
vacuum

motor

Vacuum
hose

Idle

compensator
to

intake
manifold

Hose
Air

pump
to
air
cleaner

Hose
AB
valve

to
air
cleaner

Hose
Carburetor
to
air

cleaner

Blow

by
hose
Air

cleaner
to

rocker

cover

Hose
Air

control
vaive
to
air

cleaner
California

models

only

3
To

install

reverse
the
removal

procedure

INSPECTION

1
AIR
CLEANER

ELEMENT

Viscous

paper
type
air
cleaner

ele

ment
does
not

require
any
cleaning

operation
until
it

is

replaced
periodi

cally
Brushing
or

blasting

operation

will
cause

clogging
and

result
in
enrich

ment

of
carburetor
mixture

and

should
never
be

conducted
For

reo

placement
interval
of
air

cleaner
ele

ment
refer
to
Maintenance
Sched

ule

2
HOT

AIR

CONTROL
SYSTEM

In

warm
weather
it
is

difficult
to

find

out
malfunction
of
hot
air
control

system
In

cold
wea
thee

however

malfunction
of
air
control
valve

due
to

disconnection
or

deterioration
of

vacu

um

hose
between
intake
manifold
and

vacuum
motor
and

insufficient
dura

bility
of
air
control
valve

will
cause

insufficient
automatic
control

opera

tion

for
intake
air
and

result
in

engine

disorder

including

I

Stall

or
hesitation
of

engine

oper

ation

2

Increase
in

fuel

consumption

3

uck
of

power
Engine
Fuel

These

phenomena
reveal
malfunc

tion
of
hot
air
control

system
If
these

phenomena
should
occur
check
hot

air
control

system
as

described
in
the

following
before

carrying
out

inspec

tion

of
carburetor

2
1
Vacuum

hose

Intake
manifold
to
3

way
connec

tor
3

way
connector
to

temperature

sensor
3

way
connector
to

idle
com

pensator
temperature
sensor
to
vacu

um

motor

I

Check
that

vacuum
hoses
are

se

curely
connected
in

correct

postion

2

Check
each
hose
for

cracks
or

distortion

hose

clip
for

condition

Note

Vacuum
hose

position
R
H

side
of
Nissan

mark
on
the

top
of

sensor
is
for

intake
manifold
L
U

side
of

the
mark

is
for

vacuum

motor

2
2
Vacuum

motor

I

With

engine
stopped
disconnect

fresh
air

duct

Place
a
mirror

at
the
end
of
air

cleaner
inlet

pipe
as
shown
and

check

to

see
if
air

con
trol
valve

is
in

correct

position

EF213

Fig
EF
11

Inspecting
valve

position

Air

control
valve
is
in

correct

posi

tion
if
its
under
hood
air

inlet
is

open

and
hot
air
inlet
is

closed
Check
air

control
valve

linkage
for

condition

2

Disconnect

vacuum
motor
inlet

vacuum
hose
and
connect

another

hose
to
the
inlet
to

apply
vacuum
to

vacuum
motor
Vacuum
can
be

ap

plied
by
breathing
in
the

hose
end

as

shown

Place
a
mirror

at
the

end
of
air

cleaner
inlet

pipe
and

check
to

see
if

air

control
valve

is
in
correct

position

EF
6
EF217

Fig
EF
12

Inspecting
valve

position

Correct

position
of
air

control
valve

is

the
reverse
of

paragraph
J
above
Air

control
valve
is
in
correct

position
if

under
hood
air
inlet
is

closed
and
hot

air

inlet
is

open

3
With

hot
air

inlet
in

open
posi

tion

as
described
in

paragraph
2

above

pinch
vacuum
hose
with

fingers

and
cut
off
air

from
vacuum
hose
In

this
condition
check
that
air

control

valve

maintains
the

condition
de

scribed
in

step
2

for
more
than
30

seconds
and
that
hot
air

inlet
is

open

If

diaphragm
spring
actuates
the
air

control
valve

by
its

spring
force
to

open
under
hood
air
inlet

within
30

seconds

replace
vacuum
motor
as
an

assembly
since
this

may
be

resulted

from

air
leak
at
vacuum
motor
dia

phragm

2
3
Temperature
ensor

Check

temperature
sensor
for
func

tion

by

proceeding
as
follows
Be

sure

to

keep
engine
cold
before

starting

test

I

With

engine
off

check
air

control

valve
for
condition
In

this
case
under

hood
air

inlet
is

open
Use
a
mirror

for

inspection
as
2
2
1

above

2

Start

engine
and

keep
idling

Immediately
after

engine
starting

check
air
control
valve
for

correct

position
as
described
above
In

this

case
correct

position
of

air
control

valve

is
the
reverse
of
2
2
I

under

hood
air

inlet
is

closed
and
hot

air

inlet
is

open

3
Check
that
air
control
valve

grad

ually
opens
to
under
hood
air

inlet

side
as

engine
warms

up
When
en

vironmental

temperature
around
tern

perature
sensor
is

low

spend
more

time

for

engine
warming
up
operation

to

facilitate
smooth

operation
of
air

control
valve

If
the
above
test
reveals

any
prob

lem

in
the

operation
of
air

control

valve

carry
out
the

following
test

4
Remove
air

cleaner
cover
Set

temperature
sensing
element
of
ther

mistor
or

thermometer
to
a

position

where

temperature
around
sensor
can

be

measured
In

this
case
fIx

wiring
of

thermistor
or

thermometer
on
the

bottom

surface
of
air

cleaner
with

adhesive

tape
in

such
a
manner
that

the

set

position
of

temperature
sensing

DESCRIPTION

OPERATION

DESCRIPTION

The
idle

compensator
is

basically
a

thermostatic
valve

which
functions
to

introduce
the
air

directly
from
the
air

cleaner
to
the

intake
manifold
to

compensate
for
abnormal
enrichment

of
mixture
in

high
idle

temperature

The
bi
metal

attached
to
the
idle

compensator
detects

the

temperature

of
intake
air
and

opens
or
closes
the

valve
Two

idle

compensators
having

different

temperature
characteristics

are

installed
one

opens
at
an
intake
air

temperature
of

60
to
700C
140
to

l580F

and
the
other
at
70

to
900C

158
to
1940F

OPERATION

The
construction
of
the
idle

com

pensator
is

shown
in
the

following
Engine
Fuel

element
will
not
be
affected

by
air

flow

Then
install
air
cleaner
cover

Fig
EF
13

Checking
temperature

sensor

IDLE
COMPENSATOR

CONTENTS
5

Carry
out
test
as
described
in

steps
I
2
and
3
above
When
air

control
valve

begins
to

open
to
under

hood
air
inlet
side
several
minutes

after

engine
starting
read
the

indica

tion

of
thermistor
or

thermometer
If

reading
falls
within
the

working
tern

perature

range
of

temperature
sensor

the
sensor
is

normal
If

reading
ex

ceeds
the

range

replace
the

sensor

with
new
one

Note
Before

replacing
temperature

sensor
check

idle

compensator
as

described
in

Idle

compensator

EF
7

EF
7
REMOVAL
AND
INSTALLATION

INSPECTION
EF

B

EF

8

q

EF222
1

Orifice

2
Bi
metal

3
Rubber
valve

Fig
EF

14
Structure

of
idle

compensator

Bi

metal
Intake
air

temperature

No

1
Below
600C
1400F

60
to
70
C

140
to
l580F

Above
700C

158
OF

Below
700C

1580F

70
to
900C

158
to
1940F

Above
900C
1940F
No
2

EF
7
The
idle

compensator

operates
in

response
to
the

under
hood
air

temper

ature

as
shown
below

Idle

compensator
operation

Fully
closed

Close
to

open

Fully

open

Fully
closed

Close
to

open

Fully

open

Body
Electrical

System

Horn
switch

The
horn
switch
is

integral
with

the

turn

signal
and
dimmer
switch
as

sembly
Remove
switch

assembly
as

outlined
in
Turn

Signal
and
Dimmer

Switch

IGNITION
SWITCH
BE861A

Fig
BE

3
I

Removing
ignition
switch

REMOVAL
AND

INSTALLATION

I
Disconnect

battery
ground
cable

from

battery

2
Unscrew
and
remove
escutcheon

from
the
front
of

ignition
switch

3
Withdraw

ignition
switch
and

wiring
assembly
with

spacer
from

shell
cover
as
shown
in

Figure
BE
3

4

Disconnect
wiring
connector

from
the
back
of

ignition
switch

5

Replace
ignition
switch
with
a

new
one

6
Connect

ignition
switch
to

wiring

connector

7

Position

ignition
switch
to
shell

cover

opening
install
and

tighten

escutcheon
and
secure
ignition
switch

to
shell
cover
R
terminal

1G
terminal

ST
terminal

B
terminal

8E

22
1

Voltage

regulator

2
Horn

relay

3

Headlamp
relay

4

Ignition
relay
California

only

5

Auto
choke
heater

relay

6

Compressor
relay

Au
conditioner

equipped
model

7

Floor
sensor

relay
California

only

8
Inhibitor

relay
Automatic

tran5mission

only

INSPECTION
BE683B

Fig
BE
30

ContInuity
test

Test

continuity

through
ignition

switch

by
using
test

lamp
or
ohm

meter

C

A
terminal
TERMINAL
0

F

F

B

IG

ST

A

R
KEY

FOSITlON

t

1

o

j
u

u

I

I
A

C

C

Fig
BE

32

Ignition
witch
BE6848