1977 DATSUN PICK-UP warning

j

EC231

Thermal

vacuum
valva
o

o

m
Emission

Control

System

0

o

o

o

l

l
@

The
thermal
vacuum
valve

is

mounted
in

the

engine
thermostat

housing
It

detects

engine
coolan
t

tem

perature
by
means
of
a

built
in

bi

metal
and

opensor
closes
the

vacuum

passage
in
the

thermal
vacuum

valve

mt

li

t

00
t

EC232

Fig
EC
54
Thennal

vacuum
valve
To
E

G
R
control
valve

From
carburetor

1

Spring

2
Bi
metal

3

O

ring

E
G
R

warning

system

The

E
G
R

warning
system
install
1

Diaphragm
spring

2

Diaphragm

3
Valve
shaft

4

Valve

5
Valve

Seat

6
Valve
cham
ber

Fig
EC
53
E
G

R
control
value

When
the

vacuum

passage
is

open
the

carburetor
suction

vacuum
is

applied

to
the

diaphragm
of
the
E
G
R

con

trol
valve
to

actuate
the

taper
valve

connected
to
the

diaphragm

theconsiiiictlo

nlie
thermal

vacuum
valve
is

shown
below

ed

independently
of
the

E
G
R

con

trol

system
monitors

the
distance
the

car
has
travelled
and

indicates
when

EC
22
the
E

G
R

control

system
must
be

checked

The
E
G
R

warning
system
consists

of

an
odometer
switch

detector
drive

counter
E

G
R

warning

lamp
and

harnesses

When
the

earn
in
the

odom

eter
switch
connected
to

the

speed

ometer
turns

once
for

each
OAkm
4

mile
the

contact

point
of
the
elec

trica
circuit
closes

allowing
electric

current
to
flow

through
the

magnet

coil
of

the
detector

drive
counter

Thus

energized
the

magnet
coil
ac

Wates

the
latchet
to

turn
the
c
unter

wheel

by
one

pitch
When
the

number

of

counts
reaches
50
000
the
latchet

drops
in

a

groove
provided
on
the

periphery
of

the
counter
wheel
to

activate

the
detector

drive
counter

switch

Then
the

E
G
R

warning

lamp

comes
on

indicating
that
the
E
G
R

control

system
Should
be
checked

The

detector
drive

coun
teT
is

equip

ped
with
an
odometer
which

can
tell

when
to
service

the
E

G
R
contr0
I

system

After

completing

periodic
check

reset
the
odometer
to

zero
by
hand

proceeding
as
follows

1
Remove

grommet
installed
on

the
side

surface
of

detector
drive

counter
unit

2
insert

a
bar

or
a
screwdriver

tip

into
the

hole
from

which

grommet
has

been

removed
and

press
down
knob

provided
in

the
detector
drive
counter

for

resetting

The
E

G
R

warning

lamp
comes

on

under
the

following
circumstances

1
When
the
number
of

counts
has

reached
50
000
In
this

case
the

lamp

indicates
that
E

G
R

control

system

must
be
checked

2
When

operating
starter
motor

Notes

a
It
is

an
indication
of

problem
in

the

E

G
R

warning
lamp
or

problems

in
the

point
or
in
the
harnesses
if

the

lamp
does
not

light
at

50
000

counts

b

The
E

G
R

warning
system
is

mounted

on
all
620
models

except

those

bound
for
California
and

Canada

1

1

I
I

I

1
v

v

I
I

I
I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

L
0

I

Magnet
coil

Detector
drive

counter

REMOVAL
AND

INSTALLATION

Remove
air
cleaner

before

removing

E
G
R
control

system
For
removal

and

installation
of
air

cleaner
refer
to

Air
Cleaner
section

Page
EF
S

Removal

I
E
G
R
control
valve

After

removing
the

following
parts

the
E

G
R

controi
valve
can

be
dis

mounted

Vacuum

hose
thermal
vacuum

valve
to
E
G
R

control
valve

E
G
R
control
valve

mounting
nut

Note
To
remove

vacuum
hose
flat

ten

clip
connecting
vacuum
hose
to

E
G
R
control
valve
and

pull
the

hose
off
with
hand
Emission
Control

System

Ignition
switch

E
G
R

warning
lamp

f

1
Ignition
switch

start

position

Fuse

1
A
Odometer
switch

r

I
I

I

I
v

I

I
I

i

lQ
U

1

mi

L
J

EC233

Fig
EC
55
E
G
R

warning
circuit

EC234

Fig
EC
56

Removing
KG
R
control

valve

2
E
G
R

pass
ge

After

removing
the

following

parts

the
E
G
R

passage
can
be
dismounted

Exhaust
gas
return

tube
exhaust

manifold

to
E
G
R

passage

B1ow

by
hose

cylinder
block

to

P
C
v
valve

Vacuum
hose
AB
valve
to
E
G
R

passage

E
G
R

passage
mounting
bolt

EC

23
EC541

Fig
EC
57

Removing
E
G
R

passage

3

Thermal
vacuum

valve

After

removing
the

following

parts

the
thermal
vacuum
valve
can
be
dis

mounted

Vacuum
hose

carburetor
to
ther

mal
vacuum
valve

Vacuum
hose
thermal
vacuum

valve

to
E

G
R
control
valve

Note
Drain

engine
coolant
before

dis

mounting
thermal
vacu
m
valve

Fig
EC
58

Removing
thermal

vacu
um
valve

4
E
G
R

warning
system

EC251

Detector
drive
counter

Detecfor
drive
counter
is
secured

on
the

top
of
R
H

hoodledge
panel
in

engine
room
To

remove
detector
drive

counter
disconnect
w
COJUlector

and

loosen
two
bolts

securing
detector

drive
counter
to
hoodledge

panel

2

E
G
R

warning
lamp

E
G
R

warning
lamp
is
mounted
at

the

top
cen
ter
of
instrument

pad
To

remove
E
G

R

warning
lamp
proceed

as
follows

1
Remove

masking
panel

On
models

equipped
with
radio

remove

warning
lamp
from
under
in

strument

panel

2

E
G
R

warning
lamp
is

a
twist

type

Remove

lamp
and
socket

as
an

assembly
Push
and
twist

lamp
off

can

EC554

Fig
EC
60
Removing
E
G
R

warning

lamp
Emission
Control

System

3
Odometer
switch

Odometer
switch
is
mounted
on
the

back
side
of

speedometer
Cam
in
the

odometer
switch
is
rotated

by
the

speedometer
To

dismount
odometer

switch

proceed
as
follows

I

Dismount
combination
meter
as

sembly

2
Remove
meter
front
cover
and

take
off

clips
and
screws
to

dismount

shadow

plate

3

Loosen
screws

securing
speed

ometer
to

printed
circuit

housing
then

remove

speedometer

4

Remove
two
screws

securing

odomete
switch
to
the

back
side
of

speedometer
and
detach
odometer

switch

EC239

Fig
EC
61

Removing
odometer

switch

InstaUatlon

To
install
reverse
the
removal

pro

cedure

EC24
V

r
CID

1
Detector
drive
counter

2
E
G
R
warning
lamp

3
Speedometer

Fig
EC
59
E
G
R

warning
y
tem

INSPECTION

Checking
E

G
R
control

system
in

its
mounted
conditionS

I

Make
a

thorough
visual
check
of

E

G
R
control

system
If

necessary

wipe
away
oil
to

facilitate

inspection

If

any
hoses
are
cracked
or

broken

replace

2

With

engine
running
check

E

G
R

warning
system
for

proper

function
Make
sure
that
E

G
R
warn

ing
lamp
lights
when

ignition
switch
is

turned

to
START

position
starter

mo

tor
runs
If
E
G
R

wanung
lamp
does

not

light
inspect
harnesses
and

con

nectors
or

replace
warning
lamp
Then

turn

ignition
switch
to
ON

position

and

check
the
following
items

I

If
odometer
of
detector
drive

counter
has
not
reached
50
000

counts
make
sure
that
E
G
R

warning

lamp
does
not
light

2
If
odomete
of
detector
drive

counter
has
attained
50
000
counts

make
sure
that
E
G
R

warning
lamp

lights

If

warning
lamp
does
not

light

check
harnesses
connectors
and
de

tector
drive
counter
replace
warning

lamp
or
detector
drive
counter
if

necessary

Notes

Operation
oC
E
G
R

warning
lamp

is
as
Collows

Ignition
Switch
Position
START

Detector
Drive

Counter

E
G
R

Warning
Lamp
ON

b
After

completing
inspection
of

E

G
R

control
system
be

sure
to

reset

odometer
of
detector
drive

counter
to

zero

c
This
item

applies
to
all
620
models

except
those
bound
for
California

and
Canada

3

With

engine
stopped
inspect

E
G
R
control
valve
for

any
indication

of

binding
or

sticking
by
moving
dia

phragm
of
control
valve

upwards
with

a

finger

2
When

engine
coolant

tempera

ture
is

high

I
Make

sure
that
E

G
R

control
valve

operates
when

engine
speed
is
in

creased
from
idling
to
3
000
to

3
500

rpm
Place
a

fmger
on
the

diaphragm
of
E
G
R
control

valve

to
check
for
valve

operation

2
If

E
G
R
control
valve
does
not

operate
check

as
follows

Disconnect
one
end
E

G
R
control

valve
side
of
vacuum
hose
connect

ing
thermal
vacuum
valve
to
E
G
R
Emission
Control

System

ON

Below

50
000
counts
Above

50
000
counts

OFF
ON

4
With

engine
running
inspect

E
G
R

control
valve
and
thermal
vacuo

um
valve
for
normal

operation

1
When

engine
coolant

tempera

ture

is
low

Make

sure
that
E
G
R

control
valve

does
not

operate
when

engine
speed
is

increased
from

idling
to
3
000
to

3
500

rpm

Place
a

fmger
on
the

diaphragm
of

E
G
R
control
valve
to

check
for
valve

operation

EC253

Fig
EC
62

Checking
E
G
R
control
valve

control
valve

Increase

engine
speed
from

idling
to

3
000
to
3

500

rpm

Make
su
re
that
thermal
vacu
um

valve
is

open
and
that

carburetor

vacuum
is

present
at
the
end

E

G
R
control

valve
side
of

vacu

um
hose

If
vacuum
is
weak
or

not

present
at

all

replace
thermal
vacuum
valve
If

vacuum
is

present
replace
E
G

R

control
valve

EC
25
EC254

Fig
EC

63

Checking
lhermal

vacuum
valve

If

any
difficulty
is
encountered
in

judging
the
condition
of

any

compo

nent

during
above

inspection
check

the

questionable
component
independ

ently
as

follows

E
G
R

control
valve

Dismount
E

G
R

control
valve

from

engine

I

Apply
vacuum
to

E
G
R

control

valve

referring
to
the

following
figure

If

the
valve

moves
to
full

position
it
is

normal

E
G
R

control
valve
will
remain

open
for
more

than
30

seconds
after

vacuum
has
cut

off

la

ET152

Fig
EC
64

Checking
E
G
R

control

ualue

2

Visually
check
E
G
R

control

valve
for

damage
wrinkle
or
defonna

tion

3

Clean
the

seating
surface
of

E
G
R
control
valve
with
a
brush

and

compressed
air

and
remove

foreign

matter
from
around
the
valve
and

port

REMOVAL

AND

INSPECTION

Removal
and

inspection
can
be

done

as
follows

Removal

Catalytic
converter

1

Apply
parking
brake

2

Place
wheel
lock
under
each
tire

3

Jack

up
the
vehicle

4
Remove
lower
shelter
of

catalytic

converter

5
Dismount

catalytic
converter

EC453

Fig
EC
69
Removing

catalytic

conuerter

Inspection

Preliminary
inspection

Visually
check
condition
of
all

component
parts
including

ho
s

tubes
and
wires

replace
if

necessary

Refer
to

Inspection
of
A
I
S
on

page
EC
17

Catalytic
converter

Whether

catalytic
converter
is
nor

mal
or
not
can
be
checked
by
ob

serving
variation
in

CO

percentage

The

checking

procedure
is

as
follows

Apply
parking
brake
Shift

gears

into
Neutral
for
manual
transmission

and
Neutral
or
Park
for
automatic

transmission

1

Visually
check

catalytic
converter

for

damage
or
cracks
Emission
Control

System

2
Remove
air
hose
between

5

way

connector
and
air
check
valve

Plug
the

disconnected
hose
to

prevent
dust

from

entering
Refer
to

page
ET
12

3

Check
carburetor

pipes
for

proper

connection

4

Warm

up
engine
sufficiently

5

Race

engine
1

500
to
2
000

rpm

two
or
three
times

under
no
load
then

run

engine
for
o
e
minute
at

idling

speed

6

Adjust
throttle

adjusting
screw

until

engine
attains
to

specified
speed

Refer
to

page
ET
10

7
Check

ignition
timing
If
neces

sary
adjust
it
to

specifkations
Refer

to

page
ET
10

B

Adjust
idle

adjusting
screw
until

specified
CO

percentage
is

obtained

Refer
to

page
ET
12

9

Repeat
the

adju
stment

process
as

described
in

steps
5
to
8
above

until

specified
CO

percentage
is
obtained

Note

Adjustment
in

step
9
should
be

made
ten

minutes
after

engine
has

wanned

up

10
Race

engine

1
500
to
2
000

rpm
two
or
three
times

under
no
load

and
make
sure
that

specified
CO

per

centage
is
obtained

11
Remove

cap
and
connect
air

hose
to

air
check
valve

If

idling

speed
increases

readjust
it

to

specified
speed
with
throttle
ad

justing
screw

12
WaRn

up
engine
for

about
four

minutes
at
2
000

rpm
under
no
load

13
Measure
CO

percentage
at

idling

speed
After

step
12
has
been
coin

pleted
wait

for
one
minute
before

making
CO

percentage
measurement

14
If
CO

percentage
measured
in

step
13
is
less
than
0
3

the

catalytic

converter

is
normal

15
If
CO

percentage
measured
in

step
13
is
over
0
3

recheck
A
I
S

and

replace
air
check
valve
Then

perform
inspection
steps
12
and
13

EC
27
16
If
CO

percentage
is

still
over

0
3
in

step
15

catalytic
conyerter
is

malfunctioning
Replace
catalytic
con

verter

INSTALLATION

To
install

reverse
the
removal

pro

cedure

Bolt

lightening

torque

specifications

Tightening

torque

Catalytic
converter

2
6
to
3
4

kg
m

19
to
25
ft
Ib

FLOOR

TEMPERATURE

WARNING
SYSTEM

DESCRIPTION

The
floor

temperature
warning

system
consists
of
a
floor

temperature

sensing
switch
installed

on
the
vehi

cle
s
floor
floor

temperature
relay
and

a

warning

lamp
on
the
instrument

panel
and
wires
that
connect
these

parts

When
the
floor

tempera
ture
rises
to

an
abnormal
level
the

warning
lamp

will

light
to
call
the
attention
of
the

driver
The

wiring
diagram
of
this

system
and
location
of
the

floor

temperature
sensing
switch
are
ilIus

trated
in

Figures
EC
70
and
EC
71

I
Emission

Control

System

Ignition
switch

Ignition

key
Off

T

I

I

I

Battery

I

J

77

77
Relay

J

Floor

temperature

sensing
swi

tch
Floor

temperature

warning

lamp

77
77

EC332

Fig
EC

70
Win

ng
diagram
of
floor
temperature
warning
system

r
l

J
@

1

Floor

temperature

Ij

cr

EC556

Fig
EC
71
Location

of
iJoor

temperature
sensing
switch

OPERATION

Floor

temperature
will
exceed

nor

mal
level

when

temperature
rise
in

the

exhaust

system
succeeding
the
cata

lytic
converter
is
caused

byeilher
an

engine
malfunction

or
severe

driving

conditions

Under
this
condition
the

floor

temperature
sensing
switch
turns

off

causing
the

starting
switch
line
of

the
floor

temperature
relay
to
turn
off
and
the

ignition
switch
line
to
turn
on

as
a
result
the
floor

temperature

warning

lamp
comes
on

When
the
floor

temperature
is

lower
t

an
the

specific

temperature

the

floor

temperature
sensing
switch

turns

on
The

ignition
line

of
the
floor

temperature
relay
turns
off
while
the

starting
switch
side
is
in

on
The
floor

temperature
warning

lamp
goes
out

EC
2B
The

lamp
is

functioning
sa
tis

factorily
if

it
is
remains
on

while
the

starting
motor
is
in

operation
The

lamp
goes
out
when

the

ignition

switch
is
in

IG

position

The

foUowing
chart

furnishes
the

information
on

the

relationship
be

tween

floor

temperatures

warning

lamp
and

sensing
switch

L

Contact
close

ECJ40

I

Contaclopen

ECJ41

Fig
EC
72

Operation

of
floor

t

mperature
sen6ing

6witch

REMOVAL

Floor

temperature

sensing

switch

1
Remove
seat

Seat
section
of

service
manual

2
Remove

sensing
sWitch
as
outlined
in

the

Body
and
Frame

floor

temperature

Floor

temperature
relay

From
under

relay
cover
remove

this

part
Refer
to

Figure
EC
73

Floortemperature

EC783

Fig
EC
73
Location

of
floor

ttmperature
relay

Floor
temparature
warning

lamp

Refer

to

Figure
EC
74

for
the

loca

tion
of
this

part

L

1t

1

RAt

Fig
EC
74
Location
of
floor

temperature
warning
lamp

INSTALLATION

To
install
reverse
the
order
of

rem
ovaL

INSPECTION

Floor
warning
temperature

system

Apply
parking
brake
Shift

gears

into
Neutral
foI
manual
transmission

and
Neutral
or
Park
for
automatic

transmission

1
Ensure
that
floor

temperature

warning

lamp
lights
when

ignition

switch
is
iumed

to
the
S

position

If

not
check

lamp
for
burned

bulbs

Replace
bulb
if
bulb
is
burned
out

If

bulb
is

not
burned
trace
wire
s

back
to

ignition
switch

Repair
or

replace
if

necessary

2
Be

sure
that
floor

temperature
is

cool
below
800C

1760Fj
before

carrying
out
the

following
procedure

I
Remove
rearseat

2

Ignition
switch
is

turned
to
the

IG

position

3
Ensure
that
floor

temperature

warning
lamp
goes
out

4
Heat

surrounding
areas
of
floor

temperature
sensing
switch
with
a

proper
heater
to
ensure
that
floor

temperature
warning
lamp
glows
when

floor
is
heated

to
the

specifications
as

shown
in
the
table
below
Emission
Control

System

Temperature

sensing
switch

Contact
close
Temperature

warning
lamp

Off

Contact
open
On

Note

Avoid

heating
floor

tempera

ture

sensing
switch

directly

If

lamp
does

not
glow
check
floor

temperature
sensing
switch
connector

for

continuity
with

a
circuit
tester

If

continuity
should
exist
after

heated

surrounding
areas
of
floor
tem

perature
sensing
switch

replace
tem

perature
sensing
switch

If
con

tinuity
does

not
exist

trace

the

wiring
back
to

relay
or
check
the

following
step
3

Repair
or

replace

wire
s
if

necessary

Note
The

floor

temperature
sensing

switch

may
be
heated

through
the

floor

by
a

proper
heater

3
Turn

ignition
switch
to
the

IG

position
and
disconnect
floor

temper

ature

sensing
connector
The

lamp

should
remain

on
If

not
check
floor

temperature
relay
for

continuity
with

2
00

r
I

141

J

To
floor

temperatwe

warning
lamp

2
From

S

position

3
From

IG

position

4

From

ignition
switch

5
To
floor

temperature

sensing
switch
O

When
floor

temperature

warning
lamp
lights

Check
floor

temperature
warning

lamp

1

Open
or

shorj
circuit
in

wiring

harness

2

Check
fuel

system
with

regard
to

the

following
items

Refer
to

Inspec

lion
of
Fuel

System

EC
29
Floor

temperature

Below
1050C
221
OF

Above

1050C
221
OF

a
circuit

tester

Referring
to
the

following
floor

temperature
relay
if

relay
is
normal

trace
wire
s

back
to

ignition
switch

Repair
faulty
wiring

Floor

temperature
relay

When

checking
floor

temperature

relay
for
unit

remove
it
and

proceed

as
follows

1

Check
for

continuity
between

@

and

ID
Continuity
should
exist

Check
for

continuity
between

CD

and@
Continuity
should
exist

Check
for

continuity
between

CD

and

@
Continuity
should
not

exist

2

Apply
a
12

volt
doc
across

@
and

ID
to

ensure
that

continuity
exists

between

CD
and

@
and
that

con
ti

nuity
does

not
between

CD
and

@
If

test
results
dn

not

satisfy
the
above

replace
the

floor

temperature
relay

EC344

Fig
EC
75

Checking
floor
temperature
relay

1
Float
level

2
Choke

3

Normal
fuel

supply
system
Prima

ry
and

secondary

4
Accelerator

pump

5
Power
valve

6
B
C
D
D

7
Fuel
strainer

8
Air
cleaner

3

Check

ignition
system
with

regard

to

the

following
items

Refer
to

Inspection
of

Ignition
System

1

Ignition
AMP

2
Distributor
Emission
Control

System

3

Ignition
coil

4

High
tension
code

5

Spark

plug

4

Check
idle

CO

adjustment
Refer

to

Inspection
of
Idle

CO

Adjustment
Note
Even
if
there
is

nothing

wrong

with

engine
the

warning
lamp
may

come
on
if
vebicle
is

being
driven

on
a

steep
slope

continuously
in

lower

gears
at

high
engine
speeds

EVAPORATIVE

EMISSION

CONTROL
SYSTEM

CONTENTS

DESCRIPTION

OPERATION

INSPECTION

FUEL
TANK

VAPOR
LIQUID

SEPARATOR

AND

VAPOR
VENT
LINE

DESCRIPTION

The

evaporative
emission
control

system
is

used
to

reduce

hydrocarbons

emitted
to
the

atmosphere
from
the

fuel

system
This

reduction
of

hydro
EC
30

EC

30

EC

31
CARBON

CANISTER
PURGE
CONTROL

VALVE

CARBON
CANISTER

FILTER

FUEL

TANK

VACUUM
RELIEF
VALVE
IEC
32

IEC
32

EC

32

EC
31

carbons
is

accomplished
by
activated

charcoals
in
the
carbon
canister

This

system
is
made

up
to

the

following

I

Fuel
tank
with

positive

sealing
filler

cap

@
2

Vapor
liquid
separator

3

Vapor
vent

line

4
Carbon

canister

5
Vacuum

signal
line

6
Canister

purge
line

5

OPERATION

Fuel

vapors
from

the
sealed
fuel

tank
are
led

into
the
carbon
canister
1
Fuel
tank

2
Fuel
nIler

cap
with
vacuum

relief

valve

3

liquid

vapor
separator
4

Vapor
vent
line

5

Canister

purge
line

6
Vacuum

signal
line

7
Carbon

canister

EF274

Fig
EC
76

Schematic

drawing
of
l
Iaporotive

emiaion

control6ydem

The

canister
is
fined
with
activated

charcoals

to
absorb

the
fuel

vapors

EC
30
when
the

engirie
is

at
rest
or
at

idlin
ll

See

Figure
EC

77