1998 NISSAN PICK-UP spark plugs replace

Introduction
The engine has an ECM to control major systems such as fuel
control, ignition control, idle air control system, etc. The ECM
accepts input signals from sensors and instantly drives actua-
tors. It is essential that both input and output signals are proper
and stable. At the same time, it is important that there are no
problems such as vacuum leaks, fouled spark plugs, or other
problems with the engine.
It is much more difficult to diagnose a problem that occurs inter-
mittently rather than continuously. Most intermittent problems are
caused by poor electric connections or improper wiring. In this
case, careful checking of suspected circuits may help prevent the
replacement of good parts.
A visual check only may not find the cause of the problems. A
road test with CONSULT or a circuit tester connected should be
performed. Follow the ``Work Flow'' on EC-56.
Before undertaking actual checks, take just a few minutes to talk
with a customer who approaches with a driveability complaint.
The customer can supply good information about such problems,
especially intermittent ones. Find out what symptoms are present
and under what conditions they occur. A ``Diagnostic Worksheet''
like the example on next page should be used.
Start your diagnosis by looking for ``conventional'' problems first.
This will help troubleshoot driveability problems on an electroni-
cally controlled engine vehicle.
Diagnostic Worksheet
There are many operating conditions that lead to the malfunc-
tions of engine components. A good knowledge of such condi-
tions can make troubleshooting faster and more accurate.
In general, each customer may feel differently about a given
problem. It is important to fully understand the symptoms or
conditions for a customer complaint.
Utilize a diagnostic worksheet like the one on next page in order
to organize all the information for troubleshooting.
MEF036D
SEF233G
SEF234G
SEF907L
TROUBLE DIAGNOSIS Ð IntroductionKA
EC-54

Measurement of Compression Pressure
1. Warm up engine.
2. Turn ignition switch OFF.
3. Release fuel pressure.
Refer to EC section (``Fuel Pressure Release'', ``BASIC SER-
VICE PROCEDURE'').
4. Remove all spark plugs.
5. Disconnect distributor center cable.
6. Attach a compression tester to No. 1 cylinder.
7. Depress accelerator pedal fully to keep throttle valve wide
open.
8. Crank engine and record highest gauge indication.
9. Repeat the measurement on each cylinder.
lAlways use a fully-charged battery to obtain specified
engine speed.
Compression pressure:
kPa (bar, kg/cm
2, psi)/rpm
Standard
1,324 (13.24, 13.5, 192)/300
Minimum
981 (9.8, 10, 142)/300
Difference limit between cylinders
98 (0.98, 1.0, 14)/300
10. If compression in one or more cylinders is low:
a. Pour a small amount of engine oil into cylinders through
spark plug holes.
b. Retest compression.
lIf adding oil helps compression, piston rings may be
worn or damaged. If so, replace piston rings after check-
ing piston.
lIf pressure stays low, a valve may be sticking or seating
improperly. Inspect and repair valve and valve seat.
(Refer to SDS.) If valve or valve seat is damaged
excessively, replace them.
lIf compression stays low in two cylinders that are next
to each other:
a. The cylinder head gasket may be leaking, or
b. Both cylinders may have valve component damage.
Inspect and repair as necessary.
SEM113B
COMPRESSION PRESSUREKA
EM-10

13. Install oil pump and distributor driving spindle with new gas-
ket in front cover.
a. Assemble oil pump and driving spindle, aligning punchmark
on driving spindle with oil hole.
b. Make sure that driving spindle is set as shown in figure.
14. Install distributor.
15. Make sure that No. 1 piston is set at TDC and that distribu-
tor rotor is set at No. 1 cylinder spark position.
16. Install cylinder head outside bolts.
17. Install intake manifold support.
18. Install rubber plugs as follows:
a. Apply liquid gasket to rubber plugs.
lRubber plugs should be replaced with new ones.
lRubber plugs should be installed within 5 minutes of
applying liquid gasket.
SEM395E
SEM574F.SEM574F
SEM572F
SEM596F
SEM931B
TIMING CHAINKA
Installation (Cont'd)
EM-20

Depending on annual driving distance and engine types, different basic schedules are introduced here.
Please follow the appropriate schedule for the vehicle. Furthermore, according to the weather and atmo-
spheric conditions, varying road surfaces, individual driving habits and vehicle usage, additional or more
frequent maintenance may be required, as shown in ``Maintenance Under Severe Driving Conditions''.
Periodic maintenance beyond the last period shown on the tables requires similar maintenance.
Basic Schedule for Gasoline Engine Models
Engine maintenance for vehicles which drive less than 30,000 km/year (18,000 miles/year)
Abbreviations: R= Replace, I = Inspect and correct or replace as necessary.
MAINTENANCE OPERATIONMAINTENANCE INTERVAL
Reference
page Perform at kilometer (mile) interval or month interval, whichever comes
first.km x 1,000 15 30 45 60 75 90
(Miles x 1,000) (9) (18) (27) (36) (45) (54)
Months 12 24 36 48 60 72
Engine oil (Use API SG or SH oil)*RRRRRRMA-19
Engine oil filter*RRRRRRMA-20
Drive beltsIIIIIIMA-15
Engine anti-freeze coolant (Ethylene glycol base) See NOTE (1) MA-16
Cooling systemIIIIIIMA-17
Air cleaner filter (Viscous paper type)*R MA-19
Fuel linesI I I MA-18
Fuel filter*R MA-18
Vapor linesI I I MA-22
Spark plugs (Conventional type)R R R MA-20
Ignition wiresI I MA-21
Heated oxygen sensor (Exhaust gas sensor)I I I MA-22
PCV filter*R R R MA-21
NOTE: (1) Replace at the first 90,000 km (54,000 miles) or 60 months, then every 60,000 km (36,000 miles) or 48 months,
whichever comes first.
* Maintenance item with ``*'' should be performed more frequently according to ``Maintenance Under Severe Driving Condi-
tions''.
PERIODIC MAINTENANCE
MA-5

Engine maintenance for vehicles which drive more than 30,000 km/year (18,000 miles/year)
Abbreviations: R= Replace, I = Inspect and correct or replace as necessary.
MAINTENANCE OPERATIONMAINTENANCE INTERVAL
Reference
page
Perform at kilometer (mile) interval.km x 1,000 15 30 45 60 75 90 105 120
(Miles x 1,000) (9) (18) (27) (36) (45) (54) (63) (72)
Engine oil (Use API SG or SH oil)*RRRRRRRRMA-19
Engine oil filter*RRRRRRRRMA-20
Drive beltsIIIIIIIIMA-15
Engine anti-freeze coolant (Ethylene glycol base) See NOTE (1) R MA-16
Cooling systemIIIIMA-17
Air cleaner filter (Viscous paper type)*R R MA-19
Fuel linesI I MA-18
Fuel filter*R MA-18
Vapor linesI I MA-22
Spark plugs (Conventional type)RRRRMA-20
Ignition wiresI MA-21
Heated oxygen sensor (Exhaust gas sensor)I I MA-22
PCV filter*R R MA-21
NOTE: (1) Replace at the first 90,000 km (54,000 miles), then every 60,000 km (36,000 miles).
* Maintenance item with ``*'' should be performed more frequently according to ``Maintenance Under Severe Driving Condi-
tions''.
Chassis and body maintenance for vehicles which drive more than 30,000 km/year (18,000 miles/year)
Abbreviations: R= Replace, I = Inspect and correct or replace as necessary, L = Lubricate, T = Tighten.
MAINTENANCE OPERATIONMAINTENANCE INTERVAL
Reference
page
Perform at kilometer (mile) interval.km x 1,000 15 30 45 60 75 90 105 120
(Miles x 1,000) (9) (18) (27) (36) (45) (54) (63) (72)
Headlamp aimingIIIINOTE (3)
Wheel alignment (If necessary, rotate & balance wheels)IIIIMA-35, NOTE (4)
Brake pads, discs & other brake components*IIIIMA-36
Brake linings, drums & other brake components*IIIIMA-36
Foot brake, parking brake & clutch (For free play, stroke & operation)IIIINOTE (5)
Brake booster vacuum hoses, connections & check valve I I MA-36
Brake & clutch systemsIIIIMA-32, 35
Brake & clutch fluid (For level & leaks)IIIIMA-32, 35
Brake fluid*R R MA-35
Power steering fluid & lines (For level & leaks)IIIIMA-37
Manual steering gear oil (For level & leaks)IIIIMA-38
Air bag system See NOTE (1)NOTE (6)
Manual transmission oil (Inspect for leaks or replace) I I R I MA-32
Transfer fluid and standard differential gear oil (For leaks)* I R I R MA-33, 34
Limited-slip differential (LSD) gear oil (For level and leaks)* I R I R MA-34
Steering gear, linkage, axle, suspension parts & propeller shaft*IIIIMA-37, 33
Greasing point of steering linkage, propeller shaft & sus-
pension*See NOTE (2)LLLLMA-33
Exhaust system*IIIIMA-32
Drive shaft*IIIINOTE (7)
Front wheel bearing grease (2WD models)I I NOTE (8)
Front wheel bearing grease (4WD models)* I R I R NOTE (8)
Free-running hub grease (4WD models)*IIIINOTE (9)
Body mountingsTTTTNOTE (10)
Body corrosionAnnually MA-41
NOTE: (1) Inspect at the first 10 years, and then every 2 years.
(2) The propeller shaft should be re-greased daily if it is immersed in water.
(3) ``Aiming Adjustment'' in EL section
(4) ``Front Wheel Alignment'' in FA section
(5) ``Brake Pedal and Bracket'' in BR section, ``Adjusting Clutch Pedal'' in CL section
(6) ``Maintenance Items'' in RS section
(7) ``FRONT AXLE Ð Drive Shaft'' in FA section
(8) ``Front Wheel Bearing'' in FA section
(9) ``Manual-lock Free-running Hub Ð 4WD'' and ``Auto-lock Free-running Hub Ð 4WD'' in FA section
(10) ``CAB AND REAR BODY'' in BT section
* Maintenance item with ``*'' should be performed more frequently according to ``Maintenance Under Severe Driving Condi-
tions''.
PERIODIC MAINTENANCE
Basic Schedule for Gasoline Engine Models
(Cont'd)
MA-7

Changing Oil Filter
1. Remove oil filter with a suitable tool.
WARNING:
Be careful not to burn yourself, as the engine and the engine
oil are hot.
2. Before installing a new oil filter, clean the oil filter mounting
surface on cylinder block, and coat the rubber seal of oil fil-
ter with a little engine oil.
3. Screw in the oil filter until a slight resistance is felt, then
tighten additionally more than 2/3 turn.
4. Add engine oil.
Refer to ``Changing Engine Oil'', MA-19.
Checking and Changing Spark Plugs
1. Disconnect ignition wires from spark plugs at boot.
Do not pull on the wire.
2. Remove spark plugs with spark plug wrench.
3. Clean plugs in sand blast cleaner.
4. Check insulator for cracks or chips, gasket for damage or
deterioration and electrode for wear and burning. If they are
excessively worn away, replace with new spark plugs.
Spark plug:
Make NGK
Standard type ZFR5E-11
Hot type ZFR4E-11
Cold type ZFR6E-11
SMA946C
SMA010
SMA229B
SMA017-A
SMA581C
ENGINE MAINTENANCEKA
MA-20

Use standard type spark plug for normal condition.
The hot type spark plug is suitable when fouling occurs with the
standard type spark plug under conditions such as:
lfrequent engine starts
llow ambient temperatures
The cold type spark plug is suitable when spark knock occurs
with the standard type spark plug under conditions such as:
lextended highway driving
lfrequent high engine revolution
5. Check spark plug gap.
Gap: 1.0 - 1.1 mm (0.039 - 0.043 in)
6. Install spark plugs. Reconnect ignition wires according to
numbers indicated on them.
Spark plug:
: 20-29N´m
(2.0 - 3.0 kg-m, 14 - 22 ft-lb)
Checking Ignition Wires
1. Check the high tension wires for cracks, damage, burned
terminals and for proper fit.
2. Measure the resistance of the high tension wires, by shak-
ing them and checking for intermittent breaks.
Resistance: Less than 12.2 kW/m (3.72 kW/ft)
Checking Positive Crankcase Ventilation
(PCV) System
CHECKING PCV VALVE
With engine running at idle, remove ventilation hose from PCV
valve; if valve is working properly, a hissing noise will be heard
as air passes through it and a strong vacuum should be felt
immediately when a finger is placed over valve inlet.
CHECKING VENTILATION HOSES
1. Check hoses and hose connections for leaks.
2. Disconnect all hoses and clean with compressed air. If any
hose cannot be freed of obstructions, replace.
Changing Positive Crankcase Ventilation
(PCV) Filter
Remove air cleaner cover and take out PCV filter located inside
air cleaner cover. Then install new PCV filter.
SMA476
SMA015A
SMA048
SMA587C
ENGINE MAINTENANCEKA
Checking and Changing Spark Plugs
(Cont'd)
MA-21

Measurement of Compression Pressure
1. Warm up engine.
2. Turn ignition switch OFF.
3. Release fuel pressure.
Refer to EC section (``Fuel Pressure Release'', ``BASIC SER-
VICE PROCEDURE'').
4. Remove all spark plugs.
5. Disconnect distributor center cable.
6. Attach a compression tester to No. 1 cylinder.
7. Depress accelerator pedal fully to keep throttle valve wide
open.
8. Crank engine and record highest gauge indication.
9. Repeat the measurement on each cylinder.
lAlways use a fully-charged battery to obtain specified
engine speed.
Compression pressure:
kPa (bar, kg/cm
2, psi)/rpm
Standard
1,324 (13.24, 13.5, 192)/300
Minimum
981 (9.8, 10, 142)/300
Difference limit between cylinders
98 (0.98, 1.0, 14)/300
10. If compression in one or more cylinders is low:
a. Pour a small amount of engine oil into cylinders through
spark plug holes.
b. Retest compression.
lIf adding oil helps compression, piston rings may be
worn or damaged. If so, replace piston rings after check-
ing piston.
lIf pressure stays low, a valve may be sticking or seating
improperly. Inspect and repair valve and valve seat.
(Refer to SDS.) If valve or valve seat is damaged
excessively, replace them.
lIf compression stays low in two cylinders that are next
to each other:
a. The cylinder head gasket may be leaking, or
b. Both cylinders may have valve component damage.
Inspect and repair as necessary.
SEM113B
COMPRESSION PRESSUREKA
EM-10