troubleshooting engine ISUZU KB P190 2007 Workshop Repair Manual

REAR AXLE 4B-45
TROUBLESHOOTING


Refer to this Section to quickly diagnose and repai
r
rear axle problems.
Each troubleshooting chart has three headings
arranged from left to right.
(1) Checkpoint
(2) Trouble Cause
(3) Countermeasure
This Section is divided into five sub-sections:
1. Abnormal Rear Axle Noise 1) Noise when the engine is driving the vehicle
2) Noise when the vehicle is coasting
3) Intermittent noise
4) Noise when the vehicle is turning
5) Constant noise
2. Vibration
3. Oil Leakage 1) Differential carrier leakage
2) Axle case leakage
3) Axle case to inside hub leakage
4) Axle case to inside brake drum leakage
4. Power Not Being Transmitted to the W heels (Propeller Shaft Operation is Normal)







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ISUZU KB P190 2007

Section 6 Troubleshooting ....................................................................................... ..... 786
PAGE
Section 6A Engine Mechanical .................................................................................... 806
Section 6B Engine Cooling .......................................................................... ................ 945
Section 6C Fuel System .......................................................................... ..................... 96 5
Section 6D Engine Electrical ................................................................ ....................... 1002
Section 6E Engine Control System (4JH1) ....................................................... ......... 1034
Section 6F Exhaust System ....................................................... .............................. ... 1333
Section 6H Accelerator Control ....................................................... ..............................135 3
SECTION 6
ENGINE
TA BLE OF CONTENTS
ENGINE 6
4JA1/4JH1 MODELS

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ISUZU KB P190 2007

TROUBLESHOOTING 6 – 1




BASIC INSPECTION PROCEDURE....6– 2

1. HARD STARTING ............................6– 3

1-1.Starter Motor Inoperative ..........6– 3

1-2. Starter Motor Operates But
Engine Does Not Turn Over ...........6– 3

1-3. Engine Turns Over But Does
Not Start Engine ..............................6– 4

2. UNSTABLE IDLING .........................6– 5

3. INSUFFICIENT POWER ..................6– 6

4. EXCESSIVE FUEL
CONSUMPTION..................................6– 7

5. EXCESSIVE OIL CONSUMPTION ..6– 8

6. OVERHEATING ...............................6– 9

7. WHITE EXHAUST SMOKE..............6– 9

8. DARK EXHAUST SMOKE ...............6– 10

9. OIL PRESSURE DOES NOT RISE..6– 11

10. ABNORMAL ENGINE NOISE ........6– 12

10-1. Engine Knocking ....................6– 12

10-2. Gas Leakage Noise .................6– 12

10-3. Continuous Noise ...................6– 13

10-4. Slapping Noise ........................6– 13

10-5. Excessive Turbocharger
Noise ................................................6– 14
11. ROTATING PART WEAR OF
TURBOCHARGER.............................. 6– 14

12. OIL LEAKAGE FROM
TURBOCHRGER ................................ 6– 15

13. INSUFFICIENT ACCELERATION
AND/OR LACK OF POWER DUE
TO TURBOCHARGER........................ 6– 15

14. BATTERY CHARGING AND
NOISE PROBLEM .............................. 6– 16

14-1. Battery No Charging ............... 6– 16

14-2. Battery Overcharging ............. 6– 16

14-3. Battery Under Charging ......... 6– 17

14-4. Battery Unstable Charging
Current ............................................. 6– 17

14-5. Charging System Noise ......... 6– 18

15. STARTER MOTOR PROBLEM ..... 6– 19

15-1. Starter Motor Pinion Engages
to Ring Gear But Engine Does
Not Turn Over .................................. 6– 19

15-2. Incorrect Pinion And Ring
Gear Engagement ........................... 6– 19

15-3. Starter Motor Continues To
Run After The Starter Switch Is
Turned Off........................................ 6– 20

15-4. Excessive Commutator
Sparking .......................................... 6– 20


SECTION 6
TROUBLESHOOTING
TABLE OF CONTENTS
PAGE PAGE

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6 – 2 TROUBLESHOOTING
Basic Inspection Procedure
Follow the under inspection procedure, when the problem vehicle comes workshop. Step Inspection point Inspection result YES NO
1 Check the check engine lamp Is the check engine lamp turn ON ? Go to
section
6E “On Board Diagnostic
(OBD) System Check" Go to Step 2
2 The battery fluid level and the
gravity Was the problem found? Re-charge the
battery or
replace the battery Go to Step 3
3 The engine coolant capacity Was the problem found? Replenish the
engine coolant Go to Step 4
4 The engine oil level Was the problem found? Replenish the
engine oil Go to Step 5
5 The air cleaner element Was the problem found? Clean or
replace Go to Step 6
6 The piping fixing condition (oil,
vacuum and fuel piping) Was the problem found? Return normal
condition Go to Step 7
7 The drive belt tension and break Was the problem found? Re-adjust the
tension or replace Go to Step 8
8 Go to section 6E “On Board
Diagnostic (OBD) System
Check” Was the problem found?
Verify repair Go to Step 9
9 Go to mechanical
troubleshooting chart Was the problem found?
Verify repair —


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ISUZU KB P190 2007

TROUBLESHOOTING 6 – 3
1. Hard Starting
Inspect the following items before diagnosis.
1. The battery conditions. The terminal connection condition.
The battery charge condition or battery power weakness.
2. The fan belt loosen or broken.
3. The main fuse condition (open or not).
4. Fuel quantity level.
1 –1 Starter motor inoperative
Step Action Value(s) Yes No
1 Check the starter switch. Does the starter switch work? —

Go to Step 2 Repair or
replace the
starter switch
2 Check the starter relay. Does the starter relay work? —

Go to Step 3 Repair or
replace the
starter relay
3 Check the magnetic switch. Does the magnetic switch work? —

Go to Step 4 Repair or
replace the magnetic switch
4 Check the pinion gear condition on the starter motor. Was the condition normal? —

Go to Step 5 Replace the
pinion gear
5 Check the brush wear or brush spring weakness. Was the condition normal? —

Replace the
starter motor assembly Repair or
replace the
brush or brush spring

1-2 Starter motor operates but engine does not turn over
Step Action Value(s) Yes No
1 Check the engine internal seizure. Was the engine seized? —

Repair or
replace seized parts Check other
DTC by Tech 2 and go to
indicated DTC


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6 – 4 TROUBLESHOOTING
1-3 Engine turn over but does not start engine
Incase of the fuel not being delivered to the injection pump
Step Action Value(s) Yes No
1 Check clogged, damaged the fuel piping or the
connector loosen.
Was any problem found? —

Repair replace problem parts. Go to Step 2
2 Was the over flow valve on the fuel filter closed? — Repair replace
the over flow valve Go to Step 3
3 Was the fuel filter element clogged? — Replace the
fuel filter element Go to Step 4
4 Was the fuel line air bled? — Go to Step 5 Bleed the air
5 Are any DTC stored? — Go to indicated
DTC Solved

Incase of the fuel is being delivered to the injection pump
Step Action Value(s) Yes No
1 Was the water contain in the fuel? — Replace the
fuel Go to Step 2
2 Was the fuel line air bled? — Go to Step 5 Bleed the air
3 Was the injection spray condition complete? —
Go to Step 4 Replace the
injection nozzle
4 Was the injection nozzle injection starting pressure OK? (See below)
Go to Step 5 Replace the
injection nozzle
5 Was the injection nozzle sticking? — Replace the
injection nozzle Go to Step 6
6 Are any DTC stored? — Go to indicated
DTC Solved

Injection nozzle opening pressure
1st = 19.5 MPa (199 kg/cm2, 2828 psi)

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TROUBLESHOOTING 6 – 9
6. Overheating
Step Action Value(s) Yes No
1 Was the engine coolant level OK? —
Go to Step 2 Replenish the
coolant
2 Was the water leakage or the radiator restriction found? (Include radiator cap) —
Repair or
replace the
leakage part. Go to Step 3
3 Was the fan belt slippage found? — Tension or
replace the fan belt. Go to Step 4
4 Was the fan clutch working completely? —
Go to Step 5 Replace the fan
clutch
assembly.
5 Was the oil leakage found from fan clutch? — Replace the fan
clutch
assembly Go to Step 6
6 Was the thermostat working normally? —
Go to Step 7 Replace the
thermostat.
7 Was the water pump working OK? —
Go to Step 8 Replace the
water pump assembly.
8 Was the restriction by the foreign materials in the cooling system found? For example, clog the water
hose between the cylinder body and radiator etc.. —
Clean or
replace the clog part. Go to Step 9
9 Was the water leakage found from the sealing cap
on the cylinder body? —
Replace the
sealing cap or replace the
cylinder body. Go to Step 10
10 Are any DTC stored? — Go to indicated
DTC. Solved

7. White Exhaust Smoke
Step Action Value(s) Yes No
1 Was the compression pressure OK? 3.0 MPa
(31.0 kg/cm2,
441 psi) at 200 rpm
Go to Step 2 Readjust the
valve clearance or replace the cylinder head gasket or
cylinder liner or
piston or piston ring or valve and relation parts.
2 Was the PCV (Positive Crankcase Ventilation) valve working completely? —

Go to Step 3 Repair or
replace the
PCV valve.
3 Was the turbocharger working completely? —
Go to Step 4 Replace the
turbocharger.
4 Are any DTC stored? — Go to indicated
DTC Solved


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6 – 12 TROUBLESHOOTING
10. Abnormal Engine Noise
10–1 Engine knocking
Step Action Value(s) Yes No
1 Was the injection nozzle pressure or injection spray
pattern OK? —

Go to Step 2 Replace the
injection nozzle
2 Was the compression pressure OK? 3.0 MPa
(31.0 kg/cm2,
441 psi) at 200 rpm Go to Step 3 Replace the
cylinder head gasket or
piston ring
3 Are any DTC stored? — Go to indicated
DTC Solved

10–2 Gas leakage noise
Step Action Value(s) Yes No
1 Was the exhaust pipe loose or broken? — Retighten or
replace the
exhaust pipe Go to Step 2
2 Was the exhaust manifold loose? —
Retighten or
replace the exhaust
manifold. Or replace the exhaust
manifold gasket Go to Step 3
3 Was the injection nozzle loose? — Retighten or
replace the
injection nozzle fixing bolt Go to Step 4
4 Was the cylinder head gasket broken? — Replace the
cylinder head gasket Go to Step 5
5 Are any DTC stored? — Go to indicated
DTC Solved


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6 – 14 TROUBLESHOOTING
10-5 Excessive turbocharger noise
The vibration noise (the air aspiration noise) occurred when turbocharger rotates, it is normal condition of the
turbocharger, no necessary any actions.
Step Action Value(s) Yes No
1 Was the excessive noise coming from the turbocharger? —

Go to Step 2 Go to Step 10
2 Inspect the fixing bolts and bands.
Was any problem found? —
Tighten the
loose parts Go to Step 3
3 Was the intake or exhaust system gasket damaged? — Replace the
damaged gasket. Go to Step 4
4 Inspect rotation parts condition.
Was the turbine wheel rotation rough? —
Replace the
turbocharger. Go to Step 5
5 Inspect the turbine wheel.
Was the turbine wheel rubbing against housing? —
Replace the
turbocharger. Go to Step 6
6 Was the turbine wheel damaged? — Replace the
turbocharger. Go to Step 7
7 Were there carbon deposits in the turbine or
compressor housing? —
Clean or
replace the
turbocharger. Go to Step 8
8 Inspect the oil supply condition.
Was the oil feed pipe clogged? —
Repair or
replace the oil feed pipe. Go to Step 9
9 Was the turbine shaft bearing worn? — Replace the
turbocharger. Go to Step 10
10 Are any DTC stored? — Go to indicated
DTC Solved

11. Rotating Part Wear of Turbocharger
Step Action Value(s) Yes No
1 Inspect engine oil.
Was it contaminated with foreign materials? —
Replace the
engine oil Go to Step 2
2 Was the recommended engine oil grade/viscosity
being used? API CD or
ISUZU
genuine/ 10W –30
Go to Step 3 Replace the
engine oil
3 Was the oil feed pipe restricted? — Clean or
replace the oil feed pipe Go to Step 4
4 Was the oil seal of turbocharger defective? — Replace the oil
seal Go to Step 5
5 Was the center housing oil drain passage clogged? — Clean center
housing or
replace the
turbocharger Go to Step 6
6 Was there oil sludge and/or coking on the turbine
shaft? —
Replace the
turbocharger Go to Step 7
7 Are any DTC stored? — Go to indicated
DTC Solved


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6 – 18 TROUBLESHOOTING
14-5 Charging System Noise Step Action Value(s) Yes No
1 Was “Visual/Physical Check" performed.
—

Go to Step 2 Go to
visual/physical check
2 Was there intermittent noise or continuous noise and
that could be identified clearly by increasing and
decreasing engine speed? —

Replace the bearing. Go to Step 3
3 Was there a growling sound and does this sound
stop when the connector was disconnected? —
Replace the
stator coil. Go to Step 4
4 Was intermittent sound heard when the generator
was running? —
Replace the
brush and/or slip ring. Go to Step 5
5 Was frictional sound heard when generator was
running? —
Clean the slip
ring or replace the brush. Go to Step 6
6 Are any DTC stored? — Go to indicated
DTC. Solved


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