1998 NISSAN PICK-UP check engine

DIAGNOSTIC PROCEDURE 7
Self-diagnostic results:
``IMPOSSIBLE TO PROCEED'' displayed on
CONSULT screen
CHECK CONSULT SCREEN.
1. Touch ``V.2.0 (DIESEL)'' on
``SELECT NATS SYSTEM''
screen.
2. Confirm ``IMPOSSIBLE TO
PROCEED'' displayed on CON-
SULT screen.
CHECK OPEN CIRCUIT BETWEEN
IMMU AND CONSULT.
1. Disconnect IMMU connector and CON-
SULT from data link connector.
2. Check continuity between the following
IMMU terminals and data link connec-
tor terminals.
OK
cNG
Repair harness.
CHECK SHORT CIRCUIT BETWEEN
IMMU AND CONSULT.
1. Disconnect IMMU connector and CON-
SULT from data link connector.
2. Check continuity between IMMU con-
nector terminal
V6,V7and ground.
Continuity should not exist.
3. Turn ignition switch to ON.
4. Check voltage between IMMU terminal
V6,V7and ground.
No voltage should exist.
OK
cNG
Repair harness.
Note:
If the circuit is short to
power circuit, IMMU may
be damaged. After
repairing, perform self-
diagnosis with CONSULT
again.
CHECK NATS ANTENNA AMP. POWER
SOURCE CIRCUIT.
1. Disconnect NATS antenna amp. con-
nector.
2. Turn ignition switch ``ON''.
3. Check voltage between antenna amp.
terminal
V1and ground.
Voltage: More than 4.7V
OKNG
(0V)
c
NATS antenna amp. +5V
line is short-circuited with
ground line.
Repair harness or connec-
tors.
VA
IMMU
terminalData link
connector
terminalContinuity
V7V13Yes
V6V14Yes
SEL719U
SEL470VA
SEL471VA
SEL636V
.
.
.
.
NATS (Nissan Anti-Theft System)/Diesel engine
Trouble Diagnoses (Cont'd)
EL-214

VA
CHECK POWER SUPPLY CIRCUIT FOR
IMMU.
Check voltage between terminal
V4of
IMMU and ground with CONSULT or
tester.
Voltage: Battery voltage
OK
cNG
Check the following.
l10A fuse (No.34,
located in the fusible
link and fuse box)
lHarness for open or
short between fuse and
IMMU connector
CHECK IGN SW. ON SIGNAL.
Check voltage between terminal
V3of
IMMU and ground with CONSULT or
tester.
Voltage: Battery voltage
OK
cNG
Check the following.
l10A fuse (No.23,
located in the fuse
block)
lHarness for open or
short between fuse and
IMMU connector
CHECK GROUND CIRCUIT FOR IMMU.
Check harness continuity between IMMU
terminal
V9and ground.
Continuity should exist.
OK
cNG
Repair harness.
lIMMU is malfunctioning.
1. Replace IMMU.
2. Perform system initialisation with CON-
SULT.
For the operation of system
initialisation, refer to ``CONSULT opera-
tion manual NATS V2.0 (Diesel)''.
SEL867UE
SEL868UE
SEL453VA
.
.
.
.
NATS (Nissan Anti-Theft System)/Diesel engine
Trouble Diagnoses (Cont'd)
EL-215

DIAGNOSTIC PROCEDURE 8
``NATS SECURITY IND. DOES NOT LIGHT UP''
CHECK INDICATOR POWER SUPPLY
CIRCUIT.
Check voltage between security indicator
terminal
V1and ground.
Battery voltage should exist.
OK
cNG
Check the following.
l7.5A fuse (No.6,
located in the fuse block)
lHarness for open or
short between fuse and
security indicator
Check security indicator.
OK
cNG
Replace security indicator.
PERFORM INITIALISATION.
Perform IMMU initialisation with CON-
SULT.
For the initialisation procedure, refer to
``CONSULT operation manual NATS V2.0
(Diesel)''.
Does security indicator operate after
initialisation has completed?
Yes
cNo
Check harness for open or
short between NATS
IMMU and security indica-
tor.
END
SEL638V.
.
.
NATS (Nissan Anti-Theft System)/Diesel engine
Trouble Diagnoses (Cont'd)
EL-216

Tool number
Tool nameDescriptionEngine application
KA TD
V1ED19601000
Compression gauge
V2ED19600600
Compression gauge
adapter (for glow
plug hole)
V3ED19600700
Compression gauge
adapter (for injector
hole)
V4ED19600800
Compression gauge
adapter (Useless)
NT625
Checking compression
pressure
ÐX
KV10106001*
Oil filter wrench
NT690
Removing oil filter
ÐX
KV10105800*
Chain stopper
NT010
XÐ
V1KV11101110
Valve seat remover
V2KV11103610
Adapter (Intake)
V3KV11103620
Adapter (Exhaust)
NT251A
Removing valve seat
ÐX
V1ST15243000
Valve seat drift
V2KV11103810
Adapter (Intake)
V3KV11103820
Adapter (Exhaust)
NT252A
Installing valve seat
ÐX
PREPARATION
Special Service Tools (Cont'd)
EM-5

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

Inspection
lCheck for cracks and excessive wear at roller links.
Replace chain if necessary.
Installation
1. Install crankshaft sprocket, oil pump drive gear and oil
thrower.
lMake sure that mating marks on crankshaft sprocket
face front of engine.
2. Position crankshaft so that No. 1 piston is set at TDC (Key-
way at 12 o'clock) fit timing chain to crankshaft sprocket so
that mating mark is in line with mating mark on crankshaft
sprocket.
3. Temporarily install cylinder head with new gasket. Position
camshaft so that keyway is set at 12 o'clock.
lSet timing chain by aligning its mating marks with those
of crankshaft sprocket and camshaft sprocket.
SEM204C
SEM205C
SEM589F
TIMING CHAINKA
EM-17

3. Set chain on camshaft sprocket by aligning each mating
mark. Then install camshaft sprocket to camshaft.
4. Tighten camshaft sprocket bolt.
5. Install rubber plugs. Refer to TIMING CHAIN, EM-21.
6. Check hydraulic valve lifter.
a. Push hydraulic valve lifter forcefully with your finger.
lBe sure to check it with rocker arm in its free position.
b. If valve lifter moves more than 1 mm (0.04 in), air may be
inside of it.
c. Bleed air off by running engine at 1,000 rpm under no-load
for about 20 minutes.
d. If hydraulic valve lifters are still noisy, replace them and bleed
air off again in the same manner as in step c.
7. Install rocker cover. Refer to TIMING CHAIN, EM-21.
lBe sure to avoid interference between rocker cover and
rocker arm.
8. Install intake and exhaust manifolds. Refer to ``OUTER COM-
PONENT PARTS'', EM-9.
SEM612F
SEM592F
SEM275C
CYLINDER HEADKA
Installation (Cont'd)
EM-35

7. Cut or grind valve seat using suitable tool at the specified
dimensions as shown in SDS, EM-100.
8. After cutting, lap valve seat with a lapping compound.
9. Check contact condition of valve seat.
COMBUSTION CHAMBER
Check combustion chamber for cracks and other damage. If
necessary, replace.
REPLACING COMBUSTION CHAMBER
Usually combustion chamber should not be removed.
1. Remove combustion chamber so that cylinder head cannot
be damaged.
2. Install combustion chamber.
Identification of combustion chambers
Identification mark
(on combustion chamber)Outer diameter
``D'' mm (in)Engine
3 places 37 (1.46) TD25
(1) Cool combustion chamber with dry ice for approximately 5 to
10 minutes.
WARNING:
Do not touch cooled combustion chamber with bare hand.
(2) Align combustion chamber knock pin with cylinder head
notch, and drive in combustion chamber with a soft hammer.
3. Check amount of protrusion of combustion chamber.
Protrusion:
Standard
þ0.05 to 0.10 mm (þ0.0020 to 0.0039 in)
VALVE DIMENSIONS
Check dimensions in each valve. For dimensions, refer to SDS.
When valve head has been worn down to 0.5 mm (0.020 in)
in margin thickness, replace the valve.
Grinding allowance for valve stem tip is 0.2 mm (0.008 in) or
less.
SEM633B
DEM107
.
SEM634B
SEM188A
CYLINDER HEADTD
Inspection (Cont'd)
EM-59