
108 Fuel and Engine Management
Installed view of the control unit with the passengers seat removed.
(2) Secure the Mem-Cal unit retaining clips.
Ensure that the clips locate into the Mem-Cal unit. (3) When installing a new control unit, transfer
the identification and bar code label to the new
control unit. (4) Ensure that the control unit wiring connec-
tors are securely installed to the control unit. (5) Activate the self diagnosis codes. If code 51
is displayed or the Check Engine warning lamp is
constantly illuminated, the Mem-Cal unit is not fully
installed. If the Mem-Cal uni t is installed correctly, a
fault in the Mem-Cal unit is indicated. Renew the
Mem-Cal unit as previously described.
To Check Power Supply and Earth Circuit
(1) Disconnect the control unit wiring connec-
tors and check for voltage at terminals B1 and C16.
If there is no voltage check the fusible link which
is located third from the front in the fusible link
connecting block. If the fu sible link is serviceable,
repair the open circuit in the wiring harness.
(2) Check for continuity to earth on terminals
A12, D1, D6 and also D3 and D10 on 1.8 liter
engines.
If there is no continuity check the earth connec-
tions at the right hand rear cylinder head bolts. If the
connections are clean and secure, repair the open
circuit in the wiring harness.
MEM-CAL UNIT
To Test - Code 51
If code 51 is displayed during the self diagnosis
test procedure, pr oceed as follows:
(1) Check that the Mem-Cal unit is fully inserted
in the control unit. (2) Erase the fault code memory and retest for
fault codes. (3) If code 51 is still displayed, renew the
Mem-Cal unit.
(4) Erase the fault code memory and retest for
fault codes. (5) If code 51 is still displayed, renew the control
unit.
To Remove and Install
The Mem-Cal unit is incorporated within the
control unit. Refer to the previous heading for the
removal and installation procedure.
FUEL PUMP AND EGI RELAYS
To Remove and Install
(1) Disconnect the negative battery terminals.
(2) Remove the fuse panel cover which is lo-
cated adjacent to the steering column under the
instrument cluster. (3) Remove the spare fuse holder from the fuse
panel and remove the releva nt relay from the connec-
tor. Installation is a reversal of the removal procedure.
View showing the location of the EGI and fuel pump
relays.
To Test Relays
NOTE: When testing the fuel pump relay
circuit ensure that th e EGI relay is service-
able and installed to the relay connector
(1) Remove the relevant relay as previously
described. (2) Using an ohmmeter, check for continuity
between terminals 1 and 2, and 3 and 5. Continuity should exist be tween terminals 1 and 2
but should not exist between terminals 3 and 5.
(3) Using suitable jumper leads, apply 12 volts
to terminal 1 and connect terminal 2 to a good earth
point. (4) Connect the ohmmeter between terminals 3
and 5. Continuity should exist. If continuity does not
exist, renew the relay.

Fuel and Engine Management 109
Diagram showing the identification of the relay and the relay connector terminals.
To Test Relay Circuits
(1) Remove the relevant relay as previously
described and connect the ne gative battery terminal.
(2) Connect a test lamp to earth and probe the
fuel pump relay connector terminal C or the EGI relay
connector terminal A. With the ignition switched On
the test lamp should light. If the test lamp does not light check the fuel pump
fuse and the wiring harness for continuity between the
ignition switch and the fuel pump relay connector
terminal C or EGI rela y connector terminal A.
(3) With the ignition remaining switched On,
connect the test lamp between the fuel pump relay
connector terminals C and B or the EGI relay
connector terminals A and B.
If the test lamp does not light, repair the open
circuit between terminal B and earth.
(4) When checking the EGI relay circuit, pro-
ceed to operation (9).
When checking the fuel pu mp relay circuit pro-
ceed as follows.
(5) Probe the relay connector terminal A with a
test lamp to earth. Switch the ignition On and note the
test lamp.
If the test lamp lights for 2 seconds, proceed to
step (7).
If the test lamp does not light as specified, proceed
as follows.
(6) Switch the ignition Off and backprobe the
control unit wiring connector terminal A1 with a test
lamp to earth. With the ignition switched On the test
lamp should light as previously described.
If the test lamp does not light as described, renew
the control unit.
If the test lamp does light as described, locate the
open circuit or short in the wiring harness between the
control unit wiring connector terminal Al and the
relay connector terminal A. Repair or renew the
wiring harness as necessary.
(7) With the ignition switched Off connect a
jumper lead between the relay connector terminals C
and D. (8) Switch the ignition On and listen for the
operation of the fuel pump. It should be possible to
feel vibrations in the fuel return hose. If the fuel pump is operating, the fuel pump relay
circuit can be considered serviceable.
If the fuel pump is not operating, check the wiring
harness for continuity between the fuel pump wiring
harness connector, the fuel pump relay connector
terminal D and earth. If no fault can be found, renew
the fuel pump.
(9) Probe the relay connector terminal C with a
test lamp to earth. The test lamp should light.
If the test lamp does not light, locate the open
circuit between the battery and terminal C. Check the
fusible link which is located third from the front in the
fusible link connecting block.
(10) Connect a jumper lead between the relay
connector terminals C and D and backprobe the
control unit wiring connector terminal A6 with a test
lamp to earth.
If the test lamp lights, the EGI relay circuit can be
considered serviceable.
If the test lamp does not light locate the open
circuit between the contro l unit wiring connector
terminal A6 and the relay connector terminal D.
Repair or renew the wiring harness as necessary.
COOLANT TEMPERATURE SENSOR
To Test — Codes 14 and 15
(1) Erase the self diagnosis code memory as
previously described. (2) Start and run the engine at idle speed for 60
seconds or until the ECM warning lamp lights.
(3) Stop the engine, switch the ignition On and
connect a jumper lead between terminals A and B on
the diagnostic link connect or. Note any fault codes
displayed. If codes 14 or 15 are displayed, proceed to
operation (4).
If codes 14 or 15 are not displayed, but were
displayed when the self diagnosis test procedure was
View showing the location of the coolant temperature
sensor. 1.6 liter engine.

114 Fuel and Engine Management
(6) Check the vehicle for the following:
(a) Low fuel pressure.
(b) Contaminated fuel.
(c) Vacuum leaks at the inlet manifold, engine
vacuum hoses and engine ventilation hoses. (d) Exhaust manifold leaks before the oxygen
sensor. (e) Correct MAP sensor operation.
(f) Blocked oxygen sensor metal vent cover eg.
plugged with mud etc. (g) Fuel injectors) partially blocked. Refer to a
fuel injection specialis t or a Nissan dealer.
If the above items have been checked and no
faults have been found, a faulty oxygen sensor is
indicated. Renew the oxygen sensor, run the engine
and ensure that no fault codes are set.
To Test — Code 45
(1) Run the engine until normal operating tem-
perature is attained. (2) With the ignition switched Off, connect a
jumper lead between terminals B and A on the
diagnostic link connector. (3) Start and run the engine at approximately
1 600-1 800 rpm for 2 minutes and note the ECM
warning lamp. If the ECM warning lamp is on more than off or
flashes at the rate of twice per second, proceed to the
following operation.
If the ECM warning lamp flashes evenly at the
rate of once per second an intermittent fault is
indicated. Proceed as follows:
(a) Check for faulty wiri ng connections. Check
that all wiring connectors are clean and secure. (b) Check that all earth wires are secure.
(4) Switch the engine Off and disconnect the
oxygen sensor wiring connector. (5) Using a jumper lead, connect the oxygen
sensor wiring connector to a suitable engine earth. (6) Start and run the engine at 1 600-1 800 rpm
and note the ECM warning lamp.
If the ECM warning lamp extinguishes for at least
30 seconds, proceed to operation (7).
If the ECM warning lamp flashes on more than off
or flashes at the rate of twice per second, switch the
engine Off and disconnect the control unit wiring
connectors. Using an ohmmeter, check that there is no
resistance between the co ntrol unit wiring connector
terminal D6 and earth. Repair or renew the wiring as
necessary.
If no fault can be found in the wiring harness,
renew the control unit.
NOTE: The wiring harness for terminal D6
earths through the righ t hand rear cylinder
head bolt.
(7) Check the vehicl e for the following:
(a) High fuel pressure.
(b) Leaking injector(s).
(c) Faulty ignition wiring.
(d) Charcoal canister purge system blocked or
restricted.
(e) Faulty coolant temper ature sensor circuit.
(f) Faulty MAT sensor circuit (1.8 liter engine).
(g) MAP sensor operation.
(h) Throttle position sensor operation.
If the above items have been checked and no
faults have been found, a faulty oxygen sensor is
indicated.
Renew the oxygen sensor, run the engine and
ensure that no fault codes are set.
To Remove and Install
(1) If the engine is cold, run the engine for
approximately two minutes to allow easy oxygen
sensor removal. (2) Disconnect the negative battery terminal and
the oxygen sensor connector.
View of the oxygen sensor removed from the exhaust
manifold.
(3) Remove the exhaust manifold heat shield
retaining bolts and remove the heat shield from the
engine.
(4) Remove the oxygen sensor with a short ring
spanner using care not to damage the sensor wire. Installation is a reversal of the removal procedure
with attention to the following points:
(1) When installing a sensor that has previously
been removed, coat the sen sor threads with anti-seize
compound. Nissan recommend a mixture of liquid
graphite and glass beads. (2) Install the sensor and tighten to the specified
torque. (3) Connect the electrical connector ensuring
that the wiring is secured away from the exhaust. (4) Install the heat shield and tighten the retain-
ing bolts securely. On 1.6 liter engines, ensure that the hot air inlet
tube is located correctly be tween the heat shield and
the air cleaner housing.
(5) Start the engine and check for leaks.
VEHICLE SPEED SENSOR
To Test - Code 24
(1) Check the fuel pump and meter fuses. If the
fuses are serviceable, proceed to operation (5). If a
fuse is blown, rectify the cause and renew the fuse.

Fuel and Engine Management 115
Erase the fault codes and retest for fault codes as
follows:
(2) Start and run the engine until normal oper-
ating temperature is attained. (3) Drive the vehicle at a speed of at least 80
km/h and, with the throttle closed, allow the vehicle to
decelerate until the engine speed is below 1 500 rpm.
NOTE: After rectifying any fault it will be
necessary to retest for fault codes. To test for
Code 24 the vehicle must be driven as
previously described.
(4) Switch the engine Off and connect a jumper
lead between terminals A and B on the diagnostic link
connector. Switch the ignition On and note the fault
codes. If code 24 is displayed proceed as follows. (5) Check the operation of the speedometer and
the instrument cluster warning lamps. If the speed-
ometer only is not functioning, proceed to operation
(13).
If the speedometer and the instrument cluster
warning lamps are not functioning, a fault in the
instrument cluster wiring harness is indicated. Refer
the fault to an auto electrical workshop or a Nissan
dealer.
If the speedometer is functioning, proceed as
follows:
(6) Raise the front of the vehicle and support it
on chassis stands. (7) Place the transaxle in Neutral and switch the
ignition On. (8) With the aid of assistants, slowly spin the
front wheels by hand while backprobing the control
unit wiring connector terminal A10 with a digital
voltmeter to earth. The voltage should alternate from under 1 volt to
over 10 volts.
If the voltmeter readi ng is not as specified,
proceed to operation (9).
If the voltmeter reading is as specified, the vehicle
speed sensor is operating satisfactorily, indicating an
intermittent fault was the cause of the fault code.
Proceed as follows:
(a) Check for faulty wiri ng connections. Check
that all wiring connectors are clean and secure. (b) Check that all earth c onnections are secure.
(9) Remove the instrument cluster as described
in the Electrical System section. (10) With the ignition switched On, backprobe
the control unit wiring connector terminal A10 with a
voltmeter to earth. The voltage should be over 10
volts. If the voltage is less than specified, check the
wiring harness for shorts to earth between the black
and yellow wire terminal on the instrument cluster
wiring connector and the control unit connector
terminal A10. Repair or renew the wiring harness as
necessary. If no fault can be found, renew the control
unit.
(11) With the ignition switched On, backprobe
the black and yellow wire terminal on the instrument
cluster wiring connector with a voltmeter to earth.
The voltage should be over 10 volts.
If the voltage is less than specified, locate the open
circuit between the instrument cluster black and
yellow wire terminal and the control unit wiring
connector terminal A10. Repair or renew the wiring
harness as necessary.
(12) With a test lamp connected to 12 volts,
backprobe the black wire terminals on the instrument
cluster wiring connectors. The test lamp should light.
If the test lamp does not light locate the open
circuit between the black wire terminals and earth.
Repair or renew the wiring harness as necessary.
If the test lamp does light, renew the signal
divider circuit board which is located in the instru-
ment cluster.
(13) With the ignition switched On and the
engine not running, disconnect the vehicle speed
sensor wiring connector from the harness connector.
(14) With a test lamp connected to earth, probe
the yellow wire terminal on the harness wiring con-
nector. The test lamp should light. If the test lamp does not light, locate the open
circuit between the yellow wi re terminal and the Fuel
Pump fuse. Repair or renew the wiring harness as
necessary.
(15) With a test lamp connected to 12 volts,
probe the black wire terminal on the harness wiring
connector. The test lamp should light.
If the test lamp does not light, locate the open
circuit between the black wire terminal and earth.
Repair or renew the wiring harness as necessary.
(16) Using a voltmeter measure the voltage at the
red wire terminal on the harness wiring connector.
If the voltage is 5-9 volts proceed to operation
(19).
If the voltage is over 9 vol ts proceed to operation
(18).
Installed view of the vehicle speed sensor.

117
EMISSION CONTROL
INTRODUCTION
To reduce the output level of the three primary
automotive emissions, carbon monoxide (CO), hydro-
carbons (HC) and oxides of nitrogen (NOx), and thus
comply with legislation on the maintenance of clean
air, several different emissi on control systems are used
in the Pulsar range of vehicles covered by this manual.
The systems will be discussed under the headings
( 1 ) Crankcase Ventilation System, (2) Evaporative
Control System, (3) Air Preheat System — 1.6 Liter
Engine and (4) Exhaust Control System.
1. CRANKCASE VENTILATION SYSTEM
DESCRIPTION
The crankcase ventilation system is of the closed
type and is designed to prevent crankcase vapors
being emitted into the atmosphere. Crankcase
vapors are caused by gases escaping past the piston
rings into the crankcase during the combustion pro-
cess.
The crankcase vapors are collected in the cam-
shaft housing from the cra nkcase via the various oil
drain passages and the pipe from the side of the
crankcase.
The crankcase vapors are then drawn into the
engine via a branched hose connected to the camshaft
housing oil baffle and the throttle body (1.8 liter
engines) or inlet manifold (1.6 liter engines).
At idle speed, vapors are drawn through the
small branch of the hose and into the engine.
As the engine speed increases, vapors are also
drawn into the engine via the main hose.
TO SERVICE THE SYSTEM
(1) At intervals of 40 000 km, disconnect the
small engine ventilation hose from the throttle body
or inlet manifold and check that the metering orifice
is not blocked.
If necessary, clean the orifice using compressed air
and solvent.
(2) Disconnect all the engine ventilation hoses
and check for blocking, collapsing and deterioration.
Renew the hoses as necessary.
2. EVAPORATIVE CONTROL SYSTEM
Special Equipment Required:
To Test Purge Valve — Hand vacuum pump
DESCRIPTION
The evaporative control system reduces the
amount of hydrocarbons emitted to the atmosphere
through fuel evaporation.
The vehicles covered by this manual use an
absorption regeneration system to reduce vapor loss.
The system utilizes a canister of activated charcoal to
trap and hold the fuel vapors until they can be fed
into the induction system for burning in the combus-
tion chambers.
The basic components of the evaporative control
system are a fuel tank with a sealed filler cap, a
charcoal canister with a pur ge control valve, a fuel
check valve and pipes a nd hoses to connect the
various components.
NOTE: The fuel tank filler cap is not vented
to the atmosphere but is equipped with a one
way relief valve to prevent a vacuum form-
ing in the fuel tank.
View of the engine ventilation hoses and pipe. 1.8 liter
engine.

118 Emission Control
Installed view of the charcoal canister.
When the engine is at rest, fuel vapor through
evaporation gradually fills the air space in the fuel
tank. The sealed filler cap pr events the escape of this
vapor and pressure builds up within the system,
forcing the vapor to flow into the charcoal canister
which is located in the engine compartment beneath
the windscreen wiper motor.
The fuel check valve prevents liquid fuel entering
the charcoal canister when the fuel tank is full or the
vehicle is parked on a steep incline. When the engine
is running, the vapor is drawn via a hose from the
charcoal canister to the throttle body and burnt in the
combustion chambers.
TO RENEW CHARCOAL CANISTER
(1) Suitably mark and disconnect the hoses from
the canister. (2) Release the retaining spring and remove the
canister from the engine compartment. Installation is a reversal of the removal procedure.
TO RENEW FUEL CHECK VALVE
(1) Disconnect the negative battery terminal.
(2) Raise the rear of the vehicle and support it
on chassis stands. Remove the left hand rear wheel. (3) Drain the fuel from the fuel tank using a
hand pump or a suitable siphon. Do not siphon fuel
using the mouth.
(4) Remove the hoses from the check valve.
(5) Squeeze the retaining clip and remove the
check valve from the mounting bracket. Installation is a reversal of the removal procedure.
TO SERVICE THE SYSTEM
(1) Inspect the vacuum lines and connectors for
signs of leakage, cracks and deterioration and renew
as necessary. (2) Remove the fuel tank cap and check that a
slight resistance is felt, when vacuum is applied to the
one-way relief valve in the centre of the cap. Renew the fuel tank cap if no resistance is felt or
if the valve is blocked.
(3) Inspect the fuel tank cap seal for deteriora-
tion. Renew as necessary.
Installed view of the fuel check valve as seen with the
left hand rear wheel removed.
Check the fuel filler cap seal for damage.
23Q/LDZ GAUGE
Line drawing showing a hand vacuum pump.

Emission Control 119
(4) Remove the charcoal canister as previously
described under the heading To Renew Charcoal
Canister. (5) Shake the canister, there should no audible
carbon movement. If there is, renew the canister. (6) Check the purge valve by applying 20-35
kPa of vacuum with a hand pump to the control port. Using a piece of hose, blow through the purge
hose connection. If this is not possible, renew the
canister.
Remove the vacuum source and blow air through
the purge hose connection. If this is possible, renew
the canister.
(7) Apply 20-35 kPa air pressure into the fuel
tank connector. Air should flow freely from all the
other connectors.
If poor air flow through the drain tube exists,
block off the fuel tank tube and blow compressed air
at approximately 300 kPa through the purge port.
Check the air flow and if st ill poor, renew the canister.
(8) Apply 20-35 kPa air pressure to any one of
the canister ports except th e purge valve control port
and with the other ports blocked, ensure that there are
no leaks from the canister. If leaks exist, renew the
canister. (9) Remove the fuel check valve as previously
described under the heading To Renew Fuel Check
Valve. (10) Blow through the check valve from the side
that is connected to the fu el tank hose. Considerable
resistance should be felt with only a small amount of
air passing through the valve. If no resistance is felt or
if the valve is blocked renew the fuel check valve.
(11) Blow air through the fuel check valve from
the opposite end. There should be a smooth flow of air
through the valve. If the valve is blocked, renew the
fuel check valve.
3. AIR PREHEAT SYSTEM — 1.6 LITRE
ENGINE
DESCRIPTION
To reduce emissions and improve drivability
when the engine is cold, hot air is drawn into the air
cleaner from a heat shield which partially surrounds
the exhaust manifold.
When the ambient temperature is below 30°C, the
thermal vacuum valve, which is located inside the air
cleaner housing, allows vacuum to operate a servo
actuated flap in the air cleaner intake duct. When the
flap closes, hot air is dr awn from the exhaust heat
shield, through the hot air inlet tube into the air
cleaner intake duct.
When the ambient temperature is above 30°C,
the flap in the air cleaner intake duct opens allowing
cool air to enter the air cleaner.
View of the air preheat system components. 1.6 liter
engine.
TO CHECK OPERATION
(1) When the engine is cold, use a mirror to
check that the passage from the hot air inlet tube is
closed by the flap.
(2) Start and run the engi ne at approximately
1 200 rpm. The hot air inlet passage should now be
open, allowing hot air from the exhaust heat shield to
be drawn into the air cleaner. (3) Allow the engine to idle for fifteen minutes
and inspect the position of th e air cleaner intake flap.
The flap should now be in the open position allowing
cool air to be drawn into the air cleaner and shutting
oft' air from the exhaust manifold heat shield.
TO CHECK COMPONENTS
(1) Disconnect the vacuum hose from the servo
unit and connect a vacuum pump to the unit.
When the vacuum is applied to the servo unit, the
flap in the air cleaner intake duct should close.
When the vacuum is removed, the flap should
open.
View of the air cleaner raised showing the engine
ventilation hose and the thermal vacuum valve supply
hose connection. 1.6 liter engine.

216 Electrical System
NOTE: While checking the operation of the
fusible link, loosely connect the battery-
terminal only, to safeguard against damage
to the wiring harness.
(5) If the circuit is still inoperative or the fusible
link burns out again, refer the problem to an auto-
motive electrician.
RELAY LOCATIONS
The various relays employed in the vehicle elec-
trical system are located behind the fusible links
adjacent to the washer bottle in the engine compart-
ment, on the engine compartment bulkhead, under
the windscreen wiper motor and in the fuse box at the
lower right hand side of the dashboard.
The engine compartment relays power the radia-
tor fan, horn, condenser fan, bulb check, automatic
transaxle neutral safety switch, air conditioner and
condenser motor.
Installed view of the fuse box relays.
The fuse box relays power the fuel pump, ignition,
some accessories and the el ectronic control module.
18. TRAILER WIRING
There are several brands of trailer wiring connec-
tors available with a variet y of pin configurations. The
most common is the seven pin type which provides
for two auxiliary circuits, usually used for reverse
lamps and electric trailer brakes.
Installed view of the engine compartment relays.
Installed view of the engine compartment relays.
Useful connections which can be used if the trailer to
be towed is fitted with different type plug to the towing
vehicle socket
Brylite seven pin trailer plug and socket.