wiring NISSAN PULSAR 1987 User Guide

66 Engine

View of the rear engine mounting. Automatic transaxle models.
(4) Remove the bolt retaining the exhaust
mounting to the engine mounting bracket. (5) Remove the engine mounting through bolt.
(6) Remove the bolts and nuts retaining the
engine mounting to the floor panel and remove the
mounting from the vehicle.
(7) On manual transaxle models, the torque
damper can be removed after removal of the through
bolts and nuts. (8) If necessary, remove the bolts retaining the
support bracket to the engine and withdraw the
support bracket.
Installation is a reversal of the removal procedure.

14. EXHAUST SYSTEM
TO REMOVE AND INSTAL

Engine Pipe
(1) Raise the front of the vehicle and support it
on chassis stands. (2) Remove the nuts retaining the engine pipe to
the exhaust manifold flange.

NOTE: It is advisable to soak all exhaust
system nuts and bolts wi th penetrating oil to
prevent breakage when removing.

(3) Remove the bolts from the flexible joint and
withdraw the engine pipe from the vehicle. Discard
the gasket.

Installation is a reversal of the removal procedure
with attention to the following points:

(1) Clean any carbon build up from the exhaust
flange and pipe joints. (2) Inspect the condition of the flexible joint
spring. Renew the engine pipe assembly if necessary. (3) Use a new exhaust manifold flange gasket
and coat the manifold studs with anti-seize com-
pound. (4) Ensure that all nuts and bolts are tightened
securely.
Rear System

(1) Raise the front and rear of the vehicle and
support it on chassis stands. (2) Loosen the clamp securing the tailpipe and
muffler assembly to the rear pipe. (3) Remove the mounting bolts and slide the
tailpipe and muffler assembly from the rear pipe.
NOTE; Should difficulty be experienced
when separating the exhaust pipes, they
may be cut with a hacksaw or pipe cutter if
a replacement system is to be installed.

If heat is used to loosen frozen joints take
extreme care near floor panels, fuel and
brake lines or electrical wiring.

(4) Remove the bolts from the intermediate pipe
and rear pipe mountings and lower the exhaust
system. Use care not to drop the catalytic converter.
(5) If necessary the cataly tic converter can be
removed from the intermediate pipe and the rear pipe
assembly by removing the retaining bolts.

Underbody view of the exhaust system. Underbody view of the tailpipe and muffler.

Cooling and Heating Systems 73
(1) Renew all hoses that show signs of cracking
or perishing.
(2) Before finally tightening the hose clips, en-
sure that the hoses are push ed fully onto the radiator
and are not kinked. (3) On automatic transaxle models, ensure that
the oil cooler hoses are correctly installed to the
radiator and show no signs of leakage. Check and top
up the automatic transaxle fluid as necessary.
5. COOLING FAN
The radiator cooling fan is controlled by the
electronic control unit, and on vehicles with air
conditioning, the condenser fan relay. On vehicles
with air conditioning there are two cooling fans, one
is larger than the other. The large fan is for the
radiator and the smaller fan provides extra cooling
when the air conditioning is activated. Each fan is
controlled by a separate system.

TO TEST COOLING FAN AND SYSTEM
(1) With the cooling system cold and the air
conditioning, if applicable, switched off, switch the
ignition On and confirm that the cooling fan is
stationary.

NOTE: Leave the ignition On for all tests
unless otherwise stated.

(2) In the above test, if the cooling fan rotates,
proceed as follows:

(a) Disconnect the cooling fan relay from the
rear of the engine compartment relay box.
(b) If the fan stops, backprobe terminal C1 at
the electronic control unit using an LED test lamp
connected to the positive battery terminal. If no
circuit exists, renew the cooling fan relay.

View showing the location of the diagnostic link
connector. Passengers seat removed for clarity.
If a circuit exists, check the wiring harness
between the electronic control unit and the relay for
short circuits to earth and repair if necessary. If no
short circuit is present renew the electronic control
unit.


Schematic layout of the cooling fan, coolant temper-
ature sensor and related electrical components.

Installed view of the engine compartment relays. KEY

1. To Battery
2. Fusible link
COLOUR CODE
3. Fusible link
B-Black
4. Fusible linkL- Blue
5. I
gnition relayY- Yellow
6. Fuse 20 am
pW-White
7. Coolin
g fan relayO-Orange
8. Coolin
g fan
9. Coolant tem
perature
sensor
10. To air conditionin
g
fan rela
y
11. To throttle
position
sensor
12. Control unit

74 Cooling and Heating Systems
NOTE: Refer to the Fuel and Engine Man-
agement section for the correct procedure for
backprobing the control unit.

(3) In operation (1) if the cooling fan is station-
ary proceed as follows:

(a) Connect a jumper lead between the terminals
A and B of the diagnostic link connector. (b) if the fan runs, the fan circuit is satisfactory.
If the engine is overheating check the coolant temper-
ature sensor as described in the Fuel and Engine
Management section under the appropriate codes. (c) If the fan does not run, check the fuse (6) and
the fusible link (4) show n on the illustration.
(d) Backprobe terminal C1 at the electronic
control unit using an LED t est lamp connected to the
positive battery terminal. If no circuit exists, renew
the electronic control unit. (e) If the fuse and fusible links are serviceable,
ensure that power is available at the white and pink
wires from the fuse and fusible link of the cooling fan
relay. Repair any faults in the wiring to that point if
necessary. (f) Switch the ignition Off. disconnect the
cooling fan wiring connector at the radiator and
connect power to the fan. Renew the fan if it does not
run.

(4) On air conditioned models, remove the
jumper lead from the ALDL connector if still in-
stalled, start the engine and allow it to idle. Switch the
air conditioning on and ensu re that the cooling fan
runs.

If the cooling fan is opera ting as described above
but cooling system problems still exist, refer to the
Trouble Shooting heading at the start of this section.

TO REMOVE AND INSTAL COOLING FAN
(1) Disconnect the negative battery terminal.
(2) Disconnect the cooling fa n and, if applicable,
the air conditioning fan wiring connectors at the
upper edge of the radiator. (3) On models with air conditioning, remove the
compressor hose bracket bolt from the centre of the
radiator support panel.

Dismantled view of the fans and the shroud assembly. Air conditioned model.

78 Cooling and Heating Systems
The air conditioner operates only when the engine
is running as the compressor is belt driven from the
engine.

Operating the air conditioner with the tempera-
ture control raised to a hot setting will produce
dehumidified hot air which is particularly useful for
demisting the vehicle glass.

Maximum cooling is achieved by operating the air
conditioner with the temperature control lowered
fully to the coldest setting . Operate the fan at high
speed when using the coldest temperature setting to
avoid forming ice on the evaporator.

TO REMOVE AND INSTAL HEATER UNIT
(1) Remove the dashboard as described in the
Body section. (2) Drain the cooling system as previously de-
scribed in this section. (3) Loosen the hose clamps and disconnect the
heater hoses from the heater pipes.
NOTE: If the heater hos es will not come off
the heater pipes, do not use excess force or
the heater core retaining strap will be dam-
aged. Cut the hoses from the heater pipes.

(4) Remove the steering column upper mount-
ing bolts. (5) Remove the steering column cross support
bolts and move the support towards the right hand
side of the vehicle. (6) Remove the centre support retaining bolts
and remove the centre support from the vehicle.
(7) Remove the demister duct and the right
hand side ventilator duct from the vehicle. (8) Disconnect the blower fan wiring connector
from the rear of the heater controls. (9) Remove the heater retaining bolts.
(10) On models with air conditioning, it will be
necessary to loosen the evaporator mounting bolts. (11) Working in the engine compartment, push
the heater pipe grommet through the bulkhead. (12) Maneuver the heater unit upwards slightly
and out from the bulkhead using care not to damage
the heater pipes. (13) To remove the heater core and tap assembly,
remove the screws from the retaining strap and slide
the heater core from the heater unit.
Installation is a reversal of the removal procedure
with attention to the following points:

(1 ) Before installing the heater unit to the

View of the heater unit with the dashboard, centr e support, demister duct and right hand ventilator
duct removed.

Cooling and Heating Systems
11. BLOWER FAN
TO REMOVE AND INSTAL
(1) Disconnect the negative battery terminal.
(2) Working below the glov e compartment, dis-
connect the wiring connector to the blower fan motor.
(3) Remove the bolts retaining the blower fan
motor and carefully lower the motor while disconnect-
ing the drain hose.

Installation is a reversal of the removal procedure
with attention to the following points:
( t ) Tighten all bolts securely.
(2) Check that the blow er fan operates correctly.

Dismantled view of the blower fan and associated
components.
12. AIR CONDITIONING
DESCRIPTION
The air conditioning system, when used in con-
junction with the heater, enables any reasonable tem-
perature to be achieved inside the vehicle. It can also
reduce the humidity of the incoming air, aiding
demisting even when cooling is not required.

The basic components of the air conditioning sys-
tem are an evaporator, co ndenser, compressor, re-
ceiver/dryer, expansion valve and pipes and hoses
carrying the refrigerant through the system. Various
subsidiary controls and sensors are also utilized to
protect the system against low or high pressure and
excessive temperature.

The refrigerant will boil at a very low tempera-
ture (-33 deg C) and therefore must be contained
under pressure. Escaping refrigerant can cause frost-
bite and eye damage and will produce a poisonous gas
when burnt. Also, if the system suffers a rapid loss of
refrigerant, oil from the compressor may be carried
out with the refrigerant. It is recommended that any
work requiring disconnection of the components be
referred to an au thorized dealer.

In the event of major repair s to the vehicle such as
engine removal, the compress or hoses are of sufficient


Schematic diagram of a typical air conditioning
system.
length to allow the compressor to be removed as the
engine is lowered from the engine compartment with-
out disturbing any refrigerant line connections.

If the operation of the air conditioning system is
in doubt, it is recommended that the vehicle be taken
to an authorized dealer for testing and repair.

TO CHECK REFRIGERANT CHARGE
(1) Start the engine and operate the air condi-
tioner on maximum cooling for a few minutes.
(2) Observe the flow of refrigerant through the
sight glass located at the top of the receiver/dryer. On
some models it may be necessary to use a mirror to
see the sight glass. (3) If the system is operating correctly, the sight
glass will be clear during the operation of the com-
pressor. Occasional bubbles may be seen when the
compressor cycles on and off during operation, but a
NUT j-
Bubbles in the sight glass when the air conditioner is
operating indicates a low refrigerant charge.

Fuel and Engine Management 83
the fuel pump will not operate until the oil
pressure is sufficient to extinguish the oil
pressure warning lamp. Therefore it will be
necessary to operate the starter motor for a
longer period than usual to start the engine.

(3) Faulty EFI component wiring connections:
Check that all component wiring connections are
clean and secure.
(4) Manifold absolute pressure (MAP) sensor
vacuum hose blocked or disconnected: Clear or recon-
nect the vacuum hose. (5) Fault in the ignition system: Check the
primary and secondary ignition circuits.
(6) Engine flooded: Fully depress the throttle
pedal until the engine starts. Check the coolant
temperature sensor. Check th e injector(s) for leakage.
ENGINE STARTS THEN STALLS

(1) Water in the fuel: Dr ain the fuel from the
system and renew the fuel filter.
(2) Air leakage at the inlet manifold: Check all
joints and hoses for air leaks. (3) Faulty EFI wiring connections: Check that
all component wiring connections are clean and
secure.
(4) Ignition timing incorrectly set: Check and
adjust the timing. (5) MAP sensor faulty or supply hose discon-
nected or blocked: Check the vacuum supply hose.
Check the operation of the MAP sensor.
ENGINE MISFIRES

(1) Faulty, dirty or incorrectly adjusted spark
plugs: Renew or clean and adjust the spark plugs.
(2) Condensation in the distributor cap: Dry and
examine the cap for cracks. (3) Faulty high tension leads: Check and renew
the high tension leads.

Testing the fuel system pressure using a pressure
gauge.
(4) Faulty ignition coil: Check and renew the
ignition coil.
(5) Fuel blockage: Check for blockage in the fuel
filter, lines and injector(s). (6) Low fuel pressure: Check the fuel pump and
fuel pressure regulator. (7) Water in the fuel: Dr ain the fuel from the
system and renew the fuel filter. (8) Loose fuel supply wiring connectors: Check
all connectors for tightness. (9) Faulty fuel injector: Check the connections
and test the condition of the fuel injectors.
ENGINE LACKS POWER

(1) Ignition timing incorrectly set: Check and
adjust the timing.
(2) Water in the fuel: Dr ain the fuel from the
system and renew the fuel filter.
(3) Incorrectly adjusted throttle cable: Adjust the
throttle cable.



Check the distributor cap for cracks or tracking be- tween the terminals. The air filter element should be renewed at 40 000 km
intervals. 1.8 liter engine.

86 Fuel and Engine Management
other. The fuel pressure is maintained at a constant
pressure relevant to the manifold vacuum. A dispos-
able paper element fuel filter is mounted on the engine
bulkhead.

The amount of fuel injected is relevant to the time
the injector remains open. The basic time the injector
remains open is governed by the control unit which
uses information from the various sensors to give
optimum engine efficiency for given conditions.

The idle air control (IAC) valve controls the fast
idle speed during engine warm up and maintains the
basic idle speed at a set value by compensating for
loads such as air conditioning or the selection of Drive
on automatic transaxle models.

The throttle body assembly is mounted to the
inlet manifold and controls the amount of air entering
the engine by the action of the throttle valve.

Efficient operation of the EFI system depends on
accurate signals being receiv ed by the control unit and
controlled air flow beyond the throttle valve. There-
fore it is essential that all air, fuel and electrical
connections be clean and tight.

3. SERVICE PRECAUTIONS AND
PROCEDURES

Electronic ignition systems can produce danger-
ously high voltages in both the primary and secondary
circuits. For this reason, extreme care must be taken
when working on or near the ignition system.

Do not start the engine if the battery terminals are
not clean and tight.

Do not use the fast charge or boost settings on a
battery charger to start the engine.

Do not disconnect the battery terminals while the
engine is running.

Disconnect the battery terminals before charging
the battery.

Disconnect the negative ba ttery terminal before
working on the engine management system.

Do not subject the control unit to temperatures
above 80 deg C.

Ensure that all wiring connectors are clean and
tight.

Disconnect the battery terminals and the control
unit wiring connectors before attempting any welding
operations.

Do not direct a steam cleaning or pressure
washing nozzle at engine management components
when cleaning the engine.

Ensure that the ignition is Off prior to disconnect-
ing the battery terminals, fusible links or the control
unit wiring connectors.

TO CONNECT ELECTRICAL TEST
EQUIPMENT

NOTE: Some types of tachometers, timing
lights and ignition system analysers are not
compatible with this engine management
system and may result in incorrect readings.
It is therefore recommended that the man-
ufacturer of the lest equipment be consulted
before proceeding to use the equipment.

If a test procedure requires the use of a
test lamp or voltmeter, ensure that only the
specified instrument is used to prevent mis-
leading diagnosis.

MULTIMETER
It is essential that in all tests where voltage or
resistance is to be measur ed, a digital display multi-
meter with a minimum 10 megohms impedance be
used.


The correct method of backprobing the wiring connec-
tors. The meter test probe should be modified with a piece of thin wire as shown.
All meter readings are to be performed with the
component wiring connectors installed unless other-
wise instructed. This can be done by inserting the
meter test probes from the wiring harness side of the
connector or backprobing. If the test probes are not
thin, they should be modified by attaching a thin piece
of wire to the end, giving a fine point that will not
damage the connector. Ensure that the wire is making
good contact with the probe.

If sealing plugs or boots are removed from wiring
connectors to facilitate bac kprobing, ensure that they
are correctly installed at the conclusion of the test
procedure.

To identify wiring connector terminals refer to the
wiring circuit diagrams.

Test Lamp
To avoid damage to the electronic components
when testing, the use of an LED (light emitting diode)
test lamp is recommended.

Fuel and Engine Management 87

Fuel system wiring diagram for the 1.6 liter engine.

88 Fuel and Engine Management


Fuel system wiring diagram for the 1.8 liter engine.
BR K

Fuel and Engine Management 89
The procedure for fabricating an LED test lamp is
fully described in the El ectrical System section.

If a conventional test lamp with a filament type
bulb is to be used, ensure that the current draw of the
test lamp does not exceed 0.3 amp to avoid damage to
the electronic components.

To check the current draw connect an accurate
ammeter, such as the multimeter described previ-
ously, in series with the test lamp and a battery.

If the ammeter reads less than 0.3 amp the test
lamp is suitable.

Tachometer
(1) Disconnect the resistor from the tachometer
pick-up wiring connector which is located on the
ignition coil wiring harness, and connect the positive
lead of an accurate tachometer to the brown wire
terminal in the wiring connector. (2) Connect the negative lead to a good earthing
point.

View showing the location of the tachometer pickup
wiring connector with the resistor installed.
Timing Light
(1) Connect the timing light to the engine fol-
lowing the instrument manufacturers instructions.

NOTE: Do not connect or disconnect the
timing light with the engine running as
voltage surges could damage the alternator
or control unit. Do not allow the high
tension leads to open circuit with the engine
running as damage to the engine manage-
ment system could result.

(2) Do not connect the timing light positive lead
to the alternator output terminal. Where possible,
connect the power leads of the timing light to an
external power source to prevent possible transient
voltages damaging the alternator or control unit.

4. SYSTEM DIAGNOSIS AND ADJUSTMENTS
NOTE: Due to the use of complex electronic
components in the engine management sys-

tem, the diagnosis and testing procedures
described in this section should not be
carried out by persons lacking an under-
standing of electronics and the precautions
associated with the servicing of electronic
components. It is rec ommended that should
a fault arise in the system, the vehicle be
referred to an authorized workshop.

The control unit can be damaged by
component faults not indicated by the self
diagnosis codes and the renewal of the
control unit without lo cating the cause of
the failure will result in the failure of the
replacement unit. It is for this reason that
the practice of substituting components to
isolate faults is not recommended.

Prior to performing any of the follow-
ing operations, refer to the Service Pre-
cautions and Procedures heading.

PRELIMINARY CHECKS
Prior to performing the Self Diagnosis Test Pro-
cedures, perform the following preliminary checks and
rectify any problems as necessary.

(1) Check for an adequate supply of fuel in the
fuel tank. (2) Check the wiring connectors and earth points
of all engine management components for clean,
secure connections. To prevent damage to the control
unit, disconnect the negative battery terminal before
disconnecting any engine ma nagement wiring connec-
tors. (3) Check the condition of the battery. Refer to
the Electrical System sectio n for checking procedures.
Rectify any faults as necessary. (4) Check the air cleaner element for restriction.
(5) Check for air leaks at the throttle body, inlet
manifold and all related hoses. (6) Check the fuel pump pr essure as described
later in this section. (7) Ensure that the engine is in a satisfactory
mechanical condition and is in tune. Refer to the
Engine and Engine Tune-up sections as necessary.
SELF DIAGNOSIS

This function is very useful in locating system
faults particularly intermittent problems. However,
the self diagnosis mode does not provide comprehen-
sive testing of the engine management system, and
therefore should always be used in conjunction with
the other test procedures described later, in order to
accurately locate system faults.

To Interpret Self Diagnosis Codes
Once the self diagnosis mode is activated, various
fault codes will be displayed as a series of flashes by
the ECM warning lamp on the instrument cluster.