Description
In this system, blow-by gas is sucked into the air inlet pipe through
the control valve after oil separation by oil separator in the rocker
cover.
Inspection
BLOW-BY CONTROL VALVE
Check control valve for clogging and abnormalities.
VENTILATION HOSE
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.
SEF456HA
SEC586B
Blow-by control valve
Rocker coverIntake
manifold
SEC692
CRANKCASE VENTILATION SYSTEM
EC-21
Inspection (No.2-4nozzles)
Thoroughly clean all disassembled parts with fresh kerosene or
solvent.
+If nozzle needle is damaged or fused, replace nozzle assem-
bly with a new one.
+If end of nozzle needle is seized or excessively discolored,
replace nozzle assembly.
+Check nozzle body and distance piece for proper contact. If
excessively worn or damaged, replace nozzle assembly or dis-
tance piece.
+Check distance piece and nozzle holder for proper contact. If
excessively worn or damaged, replace distance piece or nozzle
holder.
+Check nozzle spring for excessive wear or damage. If exces-
sively worn or damaged, replace it with a new spring.
Cleaning (No.2-4nozzles)
a. Do not touch the nozzle mating surface with your ®ngers.
b. To wash the nozzles, use a wooden stick and brass brush
with clean diesel fuel.
1. Remove any carbon from exterior of nozzle body (except wrap-
ping angle portion) by using Tool.
2. Clean oil sump of nozzle body using Tool.
3. Clean nozzle seat by using Tool.
This job should be performed with extra precautions, since
efficiency of nozzle depends greatly on a good nozzle seat.
SEF830
SEF831
SEF832
INJECTION NOZZLE
EC-23
Symptom Matrix Chart
SYSTEM
Ð Basic engine
control systemSYMPTOM
Reference page
Feature of symptom, Check pointHARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
KNOCK/DETONATION
LACK OF POWER
POOR ACCELERATION
HI IDLE
LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEAT/HIGH ENGINE COOLANT TEMPERATURE
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
ABNORMAL SMOKE COLOR
DEAD BATTERY (UNDER CHARGE)
Malfunction indicator lamp illuminates.
Can be detected by CONSULT?
Fuel cutNO START (with ®rst ®ring)
NO START (without ®rst ®ring)
HARD TO START WHEN ENGINE IS COLD
HARD TO START WHEN ENGINE IS HOT
AT IDLE
DURING DRIVING
WHEN DECELERATING
BLACK SMOKE
WHITE SMOKEWarranty symptom
codeAA AB AC AD AE AF AG AH AJ AK AL AM AP HA
Injection
timingAdvancedjj
++j+jj+jEC-47
Retardedjj
++j+jj+jEC-47
Electric injection pump
mainframe
++++jjjjj+jjj++jj+j jjjÐ*1
Injection nozzlejjjjjjj
+jj j++ +EC-22 *2
Glow systemjj
++ + +EC-151
Engine body
jj
++jjj+jj j++jjj+EM sec-
tion*3
EGR system
++ +EC-156
Air cleaner and ducts
++ +jMA sec-
tion*4
+; High Possibility Item
j; Low Possibility Item
*1: Insufficient or excess amount. Governor malfunction may be the cause.
*2: Depends on open-valve pressure and spray pattern.
*3: Caused mainly by insufficient compression pressure.
*4: Symptom varies depending on off-position of air duct, etc.
TROUBLE DIAGNOSIS Ð General Description
EC-48
SYSTEM
Ð ECCS systemMalfunction
SYMPTOM
Reference
page Feature of symptom
Check point
HARD/NO START/
RESTART (EXCP. HA) ENGINE STALL HESITATION/SURGING/FLAT SPOT KNOCK/DETONATION
LACK OF POWER
POOR ACCELERATION
HI IDLE
LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEAT/HIGH ENGINE COOLANT TEMPERATURE
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION ABNORMAL SMOKE COLOR
DEAD BATTERY (UNDER CHARGE) Malfunction indicator lamp illuminates.
Can be detected by CONSULT?
Fuel cut
NO START (with ®rst ®ring) NO START (without ®rst ®ring)
HARD TO START WHEN ENGINE IS COLD
HARD TO START WHEN ENGINE IS HOT
AT IDLE
DURING DRIVING
WHEN DECELERATINGBLACK SMOKE WHITE SMOKE
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM AP HAECCS
Camshaft position sensor (PUMP) cir-
cuitopen, shortjj
EC-69Tachometer malfunction
noisejjjj jj
Mass air ¯ow sensor circuitopen, ground shortjjj j
EC-74
shortjjj
Engine coolant temperature sensor
circuitopen, shortjjj jjj jjEC-79Compensation according to
engine coolant temperature does
not function.
Vehicle speed sensor circuit open, shortjjEC-83
Control sleeve position sensor circuit open, shortjjjjjjEC-87
Adjustment resistor circuit open, shortj j jjjj j jEC-92
Electric governor circuitopen, ground shortj jjjjjj
EC-96
shortjj
Injection timing control valve circuitopen, shortjjj
EC-101Injection timing cannot be con-
trolled.
ground shortjj
Accelerator switch (FC) circuitopen, shortjjj
EC-106
ground shortjj
Charge air temperature sensor circuit open, shortjEC-122
Needle lift sensor circuit open, shortjjjEC-126
Fuel cut solenoid valve circuitopen, ground shortj jjjj
EC-130
shortjjjEngine runs on after turning igni-
tion switch OFF.
Fuel temperature sensor circuit open, shortjj jj jj j jj jEC-135Compensation for amount of fuel
injected according to fuel tem-
perature does not function.
Accelerator position sensor circuit open, shortjjj jjEC-139
Crankshaft position sensor (TDC) cir-
cuitopen, shortjj jj
EC-144
noisejjjjj
TROUBLE DIAGNOSIS Ð General Description
Symptom Matrix Chart (Cont'd)
EC-49
SYSTEM
Ð ECCS systemMalfunction
SYMPTOM
Reference page Feature of symptom
Check point
HARD/NO START/
RESTART (EXCP. HA) ENGINE STALL HESITATION/SURGING/FLAT SPOT KNOCK/DETONATION
LACK OF POWER
POOR ACCELERATION
HI IDLE
LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEAT/HIGH ENGINE COOLANT TEMPERATURE
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION ABNORMAL SMOKE COLOR
DEAD BATTERY (UNDER CHARGE) Malfunction indicator lamp illuminates.
Can be detected by CONSULT?
Fuel cut
NO START (with ®rst ®ring) NO START (without ®rst ®ring)
HARD TO START WHEN ENGINE IS COLD
HARD TO START WHEN ENGINE IS HOT
AT IDLE
DURING DRIVING
WHEN DECELERATINGBLACK SMOKE WHITE SMOKE
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM AP HAECCS
Start signal circuit open, shortjjEC-163 Start control does not function.
Neutral position switch circuitopen, shortjjj
EC-170
ground shortjj
Accelerator position switch (Idle) cir-
cuitopen, ground shortjj j
EC-165
shortjjj jjAccelerator position sensor NG
signal is output.
Accelerator position switch (Full) cir-
cuitopen, shortjjj jjEC-165
Ignition switch circuitopenj jjj
EC-63
shortEngine does not stop.
Power supply for ECM circuitopenjjj
EC-63
shortjj
Throttle control solenoid valve circuitopen, short
EC-156Does not operate.
ground shortjj jDoes not stop operating.
EGRC-solenoid valve A, B circuitopen, short
EC-156
ground shortjDoes not stop operating.
Glow relay circuitopenjjjjj
EC-151Glow lamp does not turn on.
shortGlow lamp does not turn off.
ECCS relay (Self-shutoff) circuitopenjjjj
EC-63
shortjjGround short makes engine
unable to stop.
ECM, Connector circuit open, shortjjjjjjjjjjjjj jjjjjjjjjjjjEC-111
Air conditioner relay circuitopen
EC-187Air conditioner does not operate.
shortAir conditioner does not stop
operating.
Air conditioner switch circuitopen, ground short
EC-187Air conditioner does not stop
operating.
shortAir conditioner does not work.
TROUBLE DIAGNOSIS Ð General Description
Symptom Matrix Chart (Cont'd)
EC-50
TER-
MINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC Voltage and Pulse
Signal)
15 Y/L Air conditioner relayEngine is running.
Air conditioner switch is ``OFF''.BATTERY VOLTAGE
(11 - 14V)
Engine is running.
Both air conditioner switch and blower fan
switch are ``ON''.
(Compressor is operating.)0-1V
ON BOARD DIAGNOSIS LOGIC
This diagnosis continuously monitors the engine coolant temperature.
If the cooling fan or another component in the cooling system malfunctions, engine coolant temperature will
rise.
When the engine coolant temperature reaches an abnormally high temperature condition, a malfunction is
indicated.
Diagnostic Trouble
Code No.Malfunction is detected when ...Check Items
(Possible Cause)
28+Cooling fan does not operate properly (Overheat).
+Cooling fan system does not operate properly (Over-
heat).
+Engine coolant was not added to the system using
the proper ®lling method.+Harness or connectors
(The cooling fan circuit is open or shorted.)
+Cooling fan
+Radiator hose
+Radiator
+Radiator cap
+Water pump
+Thermostat
+Fan belt
+Engine coolant temperature sensor
For more information, refer to ``MAIN 12
CAUSES OF OVERHEATING'', EC-120.
CAUTION:
When a malfunction is indicated, be sure to replace the coolant following the procedure in the MA
section (``Changing Engine Coolant'', ``ENGINE MAINTENANCE''). Also, replace the engine oil.
a. Fill radiator with coolant up to speci®ed level with a ®lling speed of 2 liters per minute. Be sure to
use coolant with the proper mixture ratio. Refer to MA section (``Anti-freeze Coolant Mixture Ratio'',
``RECOMMENDED FLUIDS AND LUBRICANTS'').
b. After re®lling coolant, run engine to ensure that no water-¯ow noise is emitted.
TROUBLE DIAGNOSIS FOR ``OVER HEAT'' (DTC 28)
Cooling Fan (Overheat) (Cont'd)
EC-114
CHECK COOLING SYSTEM FOR LEAK.
Apply pressure to the cooling system with
a tester, and check if the pressure drops.
Testing pressure:
157 kPa (1.57 bar, 1.6 kg/cm
2, 23 psi)
Pressure should not drop.
CAUTION:
Higher than the speci®ed pressure may
cause radiator damage.
OK
cNG
Check the following for
leak.
+Hose
+Radiator
+Water pump
Refer to LC section (``Water
Pump'').
CHECK RADIATOR CAP.
Apply pressure to cap with a tester.
Radiator cap relief pressure:
78 - 98 kPa (0.78 - 0.98 bar, 0.8 - 1.0
kg/cm
2, 11 - 14 psi)
OK
cNG
Replace radiator cap.
CHECK THERMOSTAT.
1. Check valve seating condition at normal
room temperatures.
It should seat tightly.
2. Check valve opening temperature and
valve lift.
Valve opening temperature:
82ÉC (180ÉF) [standard]
Maximum valve lift:
More than 10 mm/95ÉC
(0.39 in/203ÉF)
3. Check if valve is closed at 5ÉC (9ÉF)
below valve opening temperature.
For details, refer to LC section (``Thermo-
stat'').
OK
cNG
Replace thermostat.
Check engine coolant temperature sensor.
Refer to ``COMPONENT INSPECTION'',
EC-82.
OK
cNG
Replace engine coolant
temperature sensor.
If the cause cannot be isolated, go to
``MAIN 12 CAUSES OF OVERHEATING''
on next page.
INSPECTION END
Perform FINAL CHECK by the following procedure after repair
is completed.
1. Warm up engine. Run the vehicle for at least 20 minutes. Pay
attention to engine coolant temperature gauge on the instrument
panel. If the reading shows an abnormally high temperature,
another part may be malfunctioning.
2. Stop vehicle and let engine idle. Check the intake and exhaust
systems for leaks by listening for noise or visually inspecting the
components.
3. Allow engine to cool and visually check for oil and coolant leaks.
Then, perform ``OVERALL FUNCTION CHECK''.
SLC754AA
SLC755AB
SLC343
.
.
.
.
.
TROUBLE DIAGNOSIS FOR ``OVER HEAT'' (DTC 28)
Cooling Fan (Overheat) (Cont'd)
EC-119
3. After-glow system
a. Connect ``S'' terminal to starter motor.
b. Start engine and read voltage.
Voltage:
Battery voltage for 5* minutes
* Engine coolant temperature is lower than 50ÉC
(122ÉF).
COMPONENT INSPECTION
Glow relay
1. Check relay for coil continuity.
Continuity should exist.
2. Check relay for proper operation.
Coil voltage Continuity Contact point
0V No OFF
12V Yes ON
Glow plug
1. Remove glow plug connecting plate.
2. Check each glow plug for continuity.
Continuity should exist:
Approximately 0.8W[at 25ÉC (77ÉF)]
+If NG, replace glow plug.
3. Install glow plug connecting plate securely.
+Do not bump glow plug heating element. If it is bumped,
replace glow plug with new one. (If glow plug is dropped
from a height of 10 cm (3.94 in), replace with new one.)
+If glow plug installation hole is contaminated with carbon,
remove using a reamer or suitable tool.
+Hand-tighten glow plug by turning it two to three times,
then tighten using a tool to speci®ed torque.
:15-20Nzm (1.5 - 2.0 kg-m, 11 - 14 ft-lb)
SEF781V
SEC564B
SEF701V
SEC565B
TROUBLE DIAGNOSES FOR NON-DETECTABLE ITEMS
Glow Control System (Cont'd)
EC-155