1987 NISSAN PULSAR ECU

Fuel and Engine Management
(8) Remove the bolts retaining the intermediate
exhaust pipe to the rear of the catalytic converter,
remove the bolt securing the exhaust mounting to the
underbody and slightly lower the intermediate exhaust
pipe. Support the intermediate pipe to prevent the
tailpipe fouling the lower bumper panel.
(9) Remove the bolts retaining the stabilizer bar
mounting brackets to the underbody and allow the
stabilizer bar to drop.
(10) Remove the bolts retaining the exhaust heat
shield to the underbody, located at the front of the
fuel tank. (11) Remove the handbrake cable mounting
bracket retaining nuts and remove the mounting
brackets from the mounting studs. (12) Remove the fuel tank retaining bolts and
maneuver the fuel tank from the vehicle. Installation is a reversal of the removal procedure
with attention to the following points:

(1) When installing the fuel tank, ensure that the
fuel pump wiring harness is directed through the
aperture in the floor. (2) Install the stabilizer bar mounting
bracket
bolts and tighten to the specified torque. Refer to the
Rear Suspension section.
(3) Using a new gasket, install the intermediate
exhaust pipe to the catalyti c converter ensuring that
the earth wire terminal is installed and tighten the
bolts securely. (4) Connect the fuel filler neck hose, the fuel
check valve hose and the breat her hose ensuring that
they are secured firmly. (5) Tighten the fuel tank drain plug to the
specified torque. (6) Connect the fuel hoses to the fuel pump,
using the marks made during removal to ensure
correct installation. (7) Install the fuel pump wiring harness and the
rubber grommet to the fuel pump cover plate. Install
the cover plate and tighten the retaining bolts se-
curely.
(8) Connect the fuel pump wiring connector
securely. (9) Check for fuel leaks as previously described.
6. AIR FLOW COMPONENTS
NOTE: Before proceeding with any of the
operations in this section, refer to the Ser-
vice Precautions and Procedures heading.

AIR CLEANER ASSEMBLY
To Renew Element
The procedure for renewing the air cleaner ele-
ment is covered in the Engine Tune-up section.

To Remove and Install — 1.8 Liter Engine
(1) Disconnect the negative battery terminal.
(2) Release the air intake hose retaining clamps,
disconnect the hose from the air cleaner upper
housing and the throttle body and remove the hose. (3) Remove the screw securing the air cleaner
intake duct to the front panel mounting bracket. (4) Remove the hexagon head screws retaining
the air cleaner mounting bracket to the right hand
inner mudguard and remove the air cleaner from the
engine compartment. (5) Release the upper housing retaining clips,
separate the upper housing from the lower housing
and remove the element. (6) Remove the air cleaner intake duct retaining
screw and disconnect the duct from the lower air
cleaner housing. (7) If necessary, remove the bolts securing the
mounting bracket to the ai r cleaner lower housing and
separate the mounting bracket from the housing. (8) Thoroughly clean the upper and lower hous-
ings in cleaning solvent and check for cracks, splits or
damage that would allow unfiltered air to enter the
engine. Renew any components as necessary.
Installation is a reversal of the removal procedure
with attention to the following points:

(1) Ensure that the r ubber insulators are in-
Dismantled view of the ai r cleaner assembly. 1.8 liter
engine.

Fuel and Engine Management 99
stalled on each side of the air cleaner mounting
bracket when installing the mounting bolts.

(2) If renewing the element, ensure that the
specified element is installed and is correctly seated in
the air cleaner housing. (3) Ensure that the air intake hose clamps are
tightened securely.
To Remove and Install — 1.6 Liter Engine

(1) Disconnect the negative battery terminal.
(2) Remove the nuts and washers retaining the
air cleaner to the throttle body assembly. (3) Release the top cover retaining clips and
remove the top cover and the air cleaner element.
Remove the air cleaner retainer from the throttle body
bolts. (4) Disconnect the engine vent hose from the air
cleaner support clamp. (5) Slightly raise the air cleaner and tilt it
towards the windscreen. Disc onnect the engine vent
hose and the temperature sensor vacuum hose from
the underside of the air cleaner. (6) Remove the air cleaner housing from the
engine.

Dismantled view of the air cleaner.
(7) Thoroughly clean the air cleaner housing and
top cover and check for cracks or damage that would
allow unfiltered air to enter the engine. Renew any
components as necessary.

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

(1) Inspect the air cleaner base gasket. Renew if
necessary. (2) Connect the engine vent hose and the tem-
perature sensor vacuum hose. (3) Install the air cleaner ensuring that the hot air
inlet tube is located correc tly between the exhaust heat
shield and the air cleaner housing. (4) When installing the top cover retaining nuts,
hand tighten only. THROTTLE BODY ASSEMBLY

To Remove and Install — 1.8 Liter Engine
(1)
Disconnect the negative battery terminal.
(2) Release the air intake hose clamp and dis-
connect the air intake hose from the throttle body. (3) Unclip the actuating rod from the throttle
lever using a small screwdriver under the ball socket if
necessary.
(4) Mark the throttle body vacuum hoses with
quick drying paint or similar and disconnect the hoses
from the throttle body. Disconnect the engine vent
hose from the throttle body. (5) Disconnect the wiring connectors from the
throttle position sensor and the IAC valve.
(6) Remove the retaining nuts and withdraw the
throttle body and gasket.
View of the throttle body and actuating rod. The rod
length must be set so that dimension A - 8—9 mm for
automatic transaxle models and 3—4 mm for manual
transaxle models.

View of the throttle body and associated components.

100 Fuel and Engine Management
Installation is a reversal of the removal procedure
with attention to the following points:

(1) Ensure that all throttle body passages are
clean. Blow out with compressed air if necessary. (2) Install the throttle body to the inlet
manifold
using a new gasket and tighten the retaining nuts to
the specified torque. (3) Connect the vacuum hoses to the throttle
body in the positions previously marked. (4) Clip the actuating rod to the throttle body
lever. Check the dimensions shown in the illustration
and adjust the rod length if necessary.
(5) Check the adjustment of the throttle cable as
described later in this section.
(6) Connect the air intake hose and tighten the
hose clamps securely.
To Remove and Install — 1.6 Liter Engine

(1) Depressurize the fuel system as previously
described. (2) Disconnect the negative battery terminal.
(3) Remove the air cleane r assembly and base
gasket as previously described. (4) Mark the fuel supply and return hoses,
release the clamps and disconnect the hoses from the
throttle body assembly. (5) Disconnect the injector, throttle position
sensor and the IAC valve wiring connectors. Remove
the injector wiring harness from the throttle body
assembly and place it to one side.
(6) Mark and disconnect the vacuum hoses from
the throttle body assembly. (7) On automatic transaxle models, disconnect
the kickdown actuating rod from the throttle linkage.
(8) Slide the outer throttle cable from the
mounting bracket, rotate the throttle linkage and disconnect the inner throttle cable from the throttle
linkage.

(9)
Remove the bolts retaining the throttle body
assembly to the inlet manifold and remove the
assembly and the gasket from the engine. (10) If necessary remove the retaining screws and
remove the fuel meter assembly, the IAC valve and
the throttle position sensor from the throttle body
assembly. Installation is a reversal of the removal procedure
with attention to the following points:

(1) If removed, install the fuel meter assembly,
the throttle position sensor and the IAC valve as
described under the relevant headings. (2) Install the throttle body assembly to the inlet
manifold using a new gasket and tighten the retaining
bolts to the specified torque. (3) Connect the vacuum ho ses to the throttle
body using the marks made on removal to ensure
correct installation. (4) On automatic transaxle models, connect the
kickdown actuating rod to the throttle linkage.
(5) Install the throttle cable and check the adjust-
ment as described later in this section.
INLET MANIFOLD

To Remove and Install
To remove and install the inlet manifold, refer to
the relevant heading in the Engine section.

IDLE AIR CONTROL (IAC) VALVE
To Test

(1) Connect an accurate tachometer to the en-
gine. (2) With the engine at normal operating temper-
ature and all accessories switched Off, note the idle
speed.
(3) With the ignition switched Off, disconnect
the IAC valve wiring connector. (4) Start the engine and check the idle speed.
If the idle speed is the same as that noted in

operation (2) proceed to operation (7).
If the idle speed is higher than noted in operation
(2) proceed as follows.

(5) With the ignition switched Off, connect the
IAC valve wiring connector.

(6) Start the engine and check the idle speed.
If the idle speed is not the same as that noted in

operation (2) proceed to operation (7).
If the idle speed is the same as noted in operation
(2) the IAC valve is operating correctly. However, if
the engine is not idling correctly carry out the
following checks.

(a) Check the air inlet system for vacuum leaks.
NOTE: Any vacuum leak will cause a fast
idle.

View of the throttle body assembly showing the loca-
tion of the base idle adjusting screw. 1.8 literengine.

Fuel and Engine Management 101


Location of the idle air control (IAC) valve. Inset shows the terminal identification.
(b) Check for a binding throttle cable, throttle
shaft or throttle position sensor. (c) Check the coolant temperature sensor resis-
tance as described later in this section. (d) Ensure that the battery terminals and the
engine earth terminals are clean and secure.
(e) Check the operation of the Park/Neutral
switch and the transaxle as described in the Automatic
Transaxle section under the Neutral Safety Switch
heading. (f) Check the spark plug gaps as described in the
Engine Tune-up section.
(g) Check the base idle speed adjustment.
(h) Check the fuel pressure and check the system
for leaks as described previously.

(I) Check the alternator voltage output as de-
scribed in the Electrical System section to ensure that
it is between 9-17 volts.

(j) Remove the IAC valve and check the bore in
the throttle body for dirt or damage.

(7) Stop the engine, switch the ignition On and
connect a jumper lead between terminals A and B on
the diagnostic link connector. (8) Disconnect the wiring connector from the
IAC valve.
(9) Check for voltage at each of the terminals on
the IAC valve wiring connector using a test lamp. If the test lamp flashes at each terminal, correct
operation of the wiring and control unit is indicated.
check for faulty IAC valve terminals. If no fault is
found renew the IAC valve.

If the test lamp is a steady light at one or more
terminals, proceed to operation (10).

If the test lamp does not flash at one or more of
the terminals proceed as follows:

(a) Check the circuit with no voltage for shorts
and for continuity between the IAC valve and the
control unit. Repair or renew the wiring harness as
necessary.
(b) Measure the resistance across the IAC valve
terminals A and B, and across terminals C and D. The resistance should be more than 30 ohms.

If the resistance is not as specified, renew the IAC
valve.

If the resistance is as specified, check for faulty
wiring connector terminals on the IAC valve and the
control unit. If no fault is found, renew the control
unit

(10) Switch the ignition Oft' and disconnect the
control unit wiring connectors. (11) Switch the ignition On and check the IAC
connector with the test lamp again. If the light is stilt
steady on one or more terminals there is a short
circuit to voltage in the wiring harness. Repair or
renew as necessary. (12) If the light is not on, check for faulty IAC
valve terminals. If no fault is found renew the IAC
valve.
To Remove and Install

(1) Disconnect the negative battery terminal.
(2) On 1.6 liter engines, remove the air cleaner
assembly as previously described. (3) Disconnect the wiring connector from the
IAC valve. (4) Remove the IAC valve retaining screws and
withdraw the IAC valve and O ring.

View of the IAC valve removed from the throttle body
assembly. 1.6 liter engine.
(5) Clean the IAC sealing surfaces to ensure
proper operation.

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

(1) When installing a new IAC valve ensure that
the part number is correct as the valve is not
interchangeable between the 1.8 and 1.6 liter engines.
(2) Measure the length of the pintle extension as
shown in the illustration. If necessary push the pintle
in by exerting firm thum b pressure with a slight
rocking motion.
NOTE: Installing (he IAC valve with the
pintle protruding too far can damage the
valve.

\(V2 Fuel and Engine Management


View of the IAC valve removed from the engine. Dimension A must not exceed 28 mm.
(3) Lubricate the IAC valve O ring with engine
oil and install the IAC valve. Tighten the retaining
screws securely.

(4). Install the IAC valve wiring connector and
the negative battery terminal.

(5) On 1.6 liter engines, install the air cleaner
assembly as previously described. (6) Run the engine until normal operating tem-
perature and idle speed are attained.
NOTE: Several minutes may elapse before
the normal idle speed is attained.

(7) Hold the throttle open at approximately
3 000 rpm for 10 seconds to reset the IAC valve.

MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSOR

To Test - Codes 33 and 34
NOTE: The following test procedure
assumes that fault codes 33 or 34 have
been
displayed during the self diagnosis test
pro-
cedure. If no codes have been displayed
but
the operation of the MAP sensor is suspect,
begin the test procedure at operation (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 connector. Note any fault codes
displayed. If code 34 is displayed, remove the jumper lead
from the diagnostic link connector, erase the self
diagnosis codes and proceed to operation (7).

If code 33 is displayed, remove the jumper lead
from the diagnostic link connector, erase the self
diagnosis code memory and proceed to operation (4).

If no codes are displayed, but codes 33 or 34
were
displayed when the self diagnosis test procedure was
originally performed, an intermittent fault is indi-
cated. Proceed as follows:

(a) Check for faulty wiring connections. Check
that all wiring connectors are clean and secure. (b) Check that all earth wires are secure.
(c) Check the vacuum hose to the MAP sensor
for deterioration or restriction.
(4) Disconnect the wiring connector from the
MAP sensor. (5) Start and run the engine at idle speed for 60
seconds or until the ECM warning lamp lights. (6) Stop the engine, switch the ignition On and
connect a jumper lead between terminals A and B on
the diagnostic link connector. Note any fault codes
displayed.
If code 33 is displayed, measure the voltage at
the
MAP sensor wiring connector terminal B with a
voltmeter to earth. Renew the control unit if the
voltage is less than 1 volt.

If the voltage is more than 1 volt, check the
wiring
harness for a short to voltage between terminal B and
the control unit wiring connector terminal Cll.
Repair or renew the wiring harness as necessary.

If code 34 is displayed, proceed as follows:
(a) Check for a restricted or leaking MAP sensor
vacuum hose.
(b) Check the wiring harness for continuity and
shorts between terminals A on the MAP sensor
connector and terminal A11 on the control unit wiring
connector. Repair or renew the wiring harness as
necessary.
If no faults are indicated in the above two checks,
proceed to operation (15).

(7) Disconnect the wiring connector from the
MAP sensor and connect a jumper lead between
terminals B and C on the wiring connector. (8) Start and run the engine at idle speed for 60
seconds or until the ECM warning lamp lights. (9) Stop the engine, switch the ignition On and
connect a jumper lead between terminals A and B on
the diagnostic link connector. Note any fault codes
displayed.
If code 33 is displayed, proceed to operation (15).
If code 34 is displayed, proceed as follows.

Location of the MAP sensor. Inset shows the terminal
identification.

Fuel and Engine Management 103
(10) Remove the jumper lead from the MAP
sensor wiring connector and measure the voltage
across terminals A and C on the MAP sensor wiring
connector.

If the voltage is below 4 volts, proceed to opera-
tion (12).

If the voltage is 4-6 volts, proceed as follows.
(11) With the ignition switched Off, disconnect
the wiring connectors from the control unit and check
the wiring harness for contin uity and shorts between
MAP sensor wiring connector terminal B and control
unit wiring connector terminal C11. Check the wiring
connectors for faults. Repair or renew the wiring
harness as necessary.

If no fault is found, renew the control unit and
retest for fault codes.

(12) Disconnect the wiring connector from the
throttle position sensor. (13) Measure the voltage across terminals A and
C on the MAP sensor wiring connector.
If the voltage is 4-6 volts, renew the throttle
position sensor as describe d later in this section.
If the voltage is below 4 volts, proceed as follows.

(14) With the ignition switched Off, disconnect
the wiring connectors from the control unit and check
the wiring harness for contin uity and shorts between
the MAP sensor wiring connector terminal C and
control unit wiring connector terminal C14. Check the
wiring connectors. Repair or renew the wiring harness
as necessary.

If no fault is found, renew the control unit and
retest for fault codes.

(15) Test the MAP sensor as follows:
(a) With the ignition switched On and the MAP
sensor wiring connector connected, measure the volt-
age across terminals A an d B by backprobing the
MAP sensor wiring connector. The voltage should be
as follows:

ALTITUDE VOLTAGE
Below 305 m .......................................... 3.8-5.5 volts
305-610 m ............................................. 3.6-5.3 volts
610-914 m ............................................. 3.5-5.1 volts
914-1 219 m .......................................... 3.3-5.0 volts
1 219-1 524 m ...................................... 3.2-4.8 volts
1 524-1 829 m ...................................... 3.0-4.6 volts
1 829-2 133 m ...................................... 2.9-4.5 volts
2 133-2 438 m ....................................... 2.8-4.3 volts
2 438-2 743 m ...................................... 2.6-4.2 volts

2 743-3 048 m ...................................... 2.5-4.0 volts
If the voltage is not as specified, renew the MAP
sensor.

(b) If the voltage is as specified, apply a 34 kPa
vacuum to the MAP sensor using a vacuum pump.
The voltage should be 1.2-2.3 volts lower than that
measured in operation (a).

If the voltage is not as specified, renew the MAP
sensor.

If no fault is found, check the vacuum supply hose
for restriction, leakage or correct installation.

To Remove and Install
(1) Disconnect the negative battery terminal.
(2) Disconnect the MAP sensor wiring connec-
tor and the vacuum hose. (3) Remove the retaining sc rews and remove the
MAP sensor from the vehicle.
Installation is a reversal of the removal procedure
with attention to the following points:

(1) If a new MAP sensor is to be installed ensure
that the colored insert inside the connector cavity
matches the color of the wiring connector.
(2) Ensure that the wiri ng connector and the
vacuum hose are connected securely.
THROTTLE CABLE
To Remove and Install

(1) On 1.6 liter engines, remove the air cleaner
assembly as previously described.
(2) Slide the outer throttle cable from the
mounting bracket, rotate the throttle linkage and
disconnect the inner throttle cable from the throttle
linkage. (3) Disconnect the throttle cable from the retain-
ing clamps in the engine compartment. (4) Disconnect the plastic re tainer from the top
of the throttle pedal and disengage the inner throttle
cable from the pedal. (5) Remove the bolts securing the throttle cable
to the bulkhead and withdraw the throttle cable. Installation is a reversal of the removal procedure.

To Adjust
(1) On 1.6 liter engines, remove the air cleaner
assembly as previously described.
(2) Remove the snap ring securing the outer
throttle cable to the insulator in the mounting bracket.
View showing the throttle cable adjustment point. 1.8
liter engine.

Fuel and Engine Management 105

DISTRIBUTOR
To Remove and Install
(1) Disconnect the negative battery terminal.
(2) Disconnect the distribu tor wiring connec-
tors.
(3) Disconnect the high tension leads from the
spark plugs. (4) Remove the distributor cap retaining screws
and remove the cap and high tension leads from the
vehicle. (5) Turn the engine in the normal direction of
rotation until the mark on the crankshaft pulley aligns
with the timing pointer and the rotor is pointing
towards the No. 1 spark pl ug lead terminal on the
distributor cap. (6) Mark the distributor body to camshaft hous-
ing relationship to aid in setting the ignition timing on
installation.
(7) Remove the distributor retaining nuts and
withdraw the distributor from the camshaft housing.
Installation is a reversal of the removal procedure
with attention to the following points:

(1) Ensure that the engine has not been rotated
while the distributor has been removed. If the engine
has been rotated, align the timing marks and ensure
that No. 1 piston is on the compression stroke.

(2) Check and renew the distributor base O ring
if the sealing quality is suspect. (3) Install the distributor to the camshaft
hous-
ing, aligning the coupling with the slot in the camshaft
and ensuring that the rotor does not move in relation
to the distributor body. Align the marks made on
removal. (4) Install and securely tighten the distributor
retaining nuts. (5) Install the distributor cap and tighten
the
retaining screws.
(6) Connect the distributor wiring connector.
(7) Connect the negative battery terminal and
check the ignition timing as previously described in
this section.
To Dismantle and Assemble
With the distributor removed from the engine and
the distributor cap removed, dismantle the distributor
as follows:

(1) Disconnect the pickup coil wiring connector
from the control module. (2) Measure the resistance between the terminals
on the pickup coil wiring connector and the distribu-
tor body. The r esistance should be infinity.
(3) Measure the resistance between the terminals


View of the distributor removed from the engine show-
ing the pickup coil connector. 0 RING RETAINING SPRING
Dismantled view of the distributor.

106 Fuel and Engine Management
on the pickup coil wiring connector. The resistance
should be 500-1 500 ohms.

If the resistance is not as specified in either of the
above tests, renew the pickup coil.

(4) Remove the retaining spring from the dis-
tributor drive coupling.
(5) Using a pin punch, remove the drive pin
from the shaft. (6) Remove the drive coupling, washer, tang
washer and thrust spring from the shaft. (7) Remove the rotor and sh aft from the distrib-
utor housing. (8) Remove the retainer from the distributor
housing and withdraw the pickup coil. (9) Remove the retaining sc rews and remove the
control module from the distributor body. (10) Carefully lever the stationary pole from the
housing using a suitable screwdriver. Assembly is a reversal of the dismantling proce-
dure with attention to the following points:

(1) Ensure that the mating surfaces of the dis-
tributor housing and the control module are clean.
(2) Apply a silicone heat sink compound to the
surfaces between the control module and the distrib-
utor housing.
IGNITION COIL

To Test
(1) Disconnect the grey wiring connector and the
black wiring connector from the ignition coil in that
order. (2) Measure the resistance between coil terminal
I and the coil body. There should be a high resistance. (3) Measure the resistance between coil termi-
nals 2 and 4. There should be a low resistance. (4) Measure the resistance between coil terminal
3 and the high tension termin al. The resistance should
be other than infinity.
If any of the tests indicate a fault, renew the
ignition coil.

To Remove and Install
(1) Disconnect the negative battery terminal.
(2) Disconnect the grey wiring connector and the
black wiring connector from the ignition coil in that
order. Disconnect the high tension lead. (3) Remove the coil mounting bracket retaining
bolts and remove the coil and bracket from the
engine. Installation is a reversal of the removal procedure.

ELECTRONIC SPARK TIMING
To Test - Code 42

(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 connector . Note any fault codes
displayed. If code 42 is displayed, proceed to operation (4).

If code 42 is not displayed, but was displayed
when the self diagnosis test procedure was originally
performed, 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) With the ignition switched Off, disconnect
the control unit wiring connectors. (5) With the ignition switched On, measure the
resistance between the contro l unit wiring connector
terminal D4 and a good earthing point. The resistance
should be less than 500 ohms.
If the ohmmeter reading is as specified, check the
wiring harness between the distributor 4 pin wiring
connector terminal D and the control unit wiring
connector terminal D4 for continuity. Repair or
renew the wiring harness as necessary. Also ensure
that the distributor 4 pin wiring connector is making
good contact when connected to the distributor.

If no fault can be found, renew the ignition
control module.

If the resistance is as specified proceed as follows.
(6) With the lead of a test lamp connected to the
positive battery terminal, backprobe the control unit
wiring connector terminal D5.

If the test lamp does not light, proceed to
operation (7).

If the test lamp lights, disconnect the 4 pin wiring
connector from the distributor. If the test lamp
remains illuminated check the wiring harness between
the distributor 4 pin wiring connector terminal B and
the control unit wiring connector terminal D5 for
shorts to earth. Repair or renew the wiring harness as
necessary. If the test lamp extinguishes, renew the
ignition system control module.

(7) Connect an ohmmeter between the control
Installed view of the ignition coil showing the coil
terminal identification.