troubleshooting engine ISUZU KB P190 2007 Workshop User Guide

TROUBLESHOOTING 6 – 19
15. Starter Motor Problem
Visual/physical check the following items before diagnosis.
The battery terminals connection condition.
The ground connection condition.
The starter motor or the battery fastener condition.
The battery fluid level and specific gravity.
15-1 Starter motor pinion engages to ring gear but engine does not turn over
Step Action Value(s) Yes No
1 Was “Visual/Physical Check" performed.
—

Go to Step 2 Go to
visual/physical check
2 Check the contact condition between the brush and
the commutator.
Was the brush and the commutator contact
intermittent? —
Replace the
brush or repair the
commutator. Go to Step 3
3 Were the brush and the commutator contact faces
dirty?
—

Clean contact face Go to Step 4
4 Was the pinion clutch slipped? — Replace the
pinion clutch Go to Step 5
5 Inspect the armature field coil.
Was there an open circuit or a short circuit in the
armature field coil? —
Repair or
replace the
armature field coil. Go to Step 6
6 Are any DTC stored? — Go to indicated
DTC. Solved

15-2 Incorrect pinion and ring gear engagement
Step Action Value(s) Yes No
1 Was “Visual/Physical Check" performed.
—

Go to Step 2 Go to
visual/physical check
2 Inspect the pinion and the ring gear teeth.
Were the pinion and/or the ring gear teeth worn or
broken? —

Replace the wron parts. Go to Step 3
3 Inspect the pinion gear return movement.
Was the pinion gear return movement incorrect? —
Adjust or
replace the movement parts. Go to Step 4
4 Are any DTC stored? — Go to indicated
DTC. Solved


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ISUZU KB P190 2007

6A – 32 ENGINE MECHANICAL









































COMPRESSION PRESSURE
MEASUREMENT
1. Start the engine and allow it to idle until the coolant
temperature reaches 70 – 80 °C (158 – 176 °F).
2. Remove the following parts.
• Leak off pipe
• Injection nozzle holder bracket
• Injection nozzle holder
3. Install the following parts.
• Set the adapter and compression gauge (SST) to
the No.1 cylinder injection nozzle hole.
• Injection nozzle holder bracket

Injection nozzle holder bracket Bolt Torque
N·m (kg·m /lb·ft)
37 (3.8/27)

Compression Gauge: 5-8840-2675-0
Adapter; Compression Gauge: 5-8531-7001-0


4. Turn the engine over with the starter motor and take the compression gauge reading.

Compression Pressure MPa (kg/cm
2 /psi) at 200 rpm
Standard Limit
3.0 (31.0/441) 2.1 (21.7/309)




5. Repeat the procedure (Steps 3 and 4) for the
remaining cylinders.
If the measured value is less than the specified limit,
refer to “Troubleshooting” in this Manual.
F06XL056
901R100003

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6A-12 ENGINE MECHANICAL (4JK1/4JJ1)
Turbocharger Troubleshooting
Condition Possible Cause Correction
Air leakage from intake pipe rubber
hose Repair
Air leakage from intake cover Repair
Clogged intercooler cooling section Clean
Clogged air cleaner element Clean or replace
Intake throttle valve stuck
Repair or replace
Turbine and housing contact
(Interference) Replace
Excessive carbon deposit near
turbine exhaust port that interferes
with turbine Clean or repair
Rough turbine shaft rotation Repair or replace
Engine has less than normal power
Damaged turbine blade Repair or replace
Oil leakage from turbocharger oil
seal Repair or replace
Clogged turbocharger oil return
pipe Repair
Clogged center housing oil
passages Repair or replace
Blue exhaust smoke
Engine oil deterioration Change engine oil
Gas leakage from intake or
exhaust system Repair
Turbine and housing contact
(Interference) Repair or replace
Damaged turbine blade
Replace
Noisy turbocharger operation
Turbine shaft bearing abrasion or
scoring Repair or replace
Engine oil deterioration
Change engine oil
Clogged turbocharger oil feed pipe Repair
Excessive rotating part wear
Low engine oil pressure Repair


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ENGINE ELECTRICAL (4JK1/4JJ1) 6D-1
SECTION 6D
ENGINE ELECTRICAL
TABLE OF CONTENTS

Charging System ................................................ 6D-2
Servicing Cautions .......................................... 6D-2
Important Generator Components and
Function.......................................................... 6D-2
Troubleshooting .............................................. 6D-5
Diagnosis......................................................... 6D-7
Specifications .................................................. 6D-8
Unit Se rv ic ing (4 JJ 1) ....................................... .... ..6D -9
Disassembly .................................................... 6D-10
Inspection and Repair ..................................... 6D-11 Rotor Assembly ........................................... 6D-11
Stator Coil .................................................... 6D-12
Brushes ....................................................... 6D-12
Rectifier ....................................................... 6D-13
Regulator Assembly..................................... 6D-13
Measuring Procedure .................................. 6D-13
Reassembly..................................................... 6D-14
Final Assembly ................................................ 6D-14
Starter Motor ...................................................... 6D-15 Starting Circuit Diagram .................................. 6D-15
Removal and Installation ................................. 6D-15 Important Operations – Removal................. 6D-15
Important Operations – Installation.............. 6D-15
Disassembly .................................................... 6D-16 Disassembly Steps ...................................... 6D-16
Important Operations ................................... 6D-17
Inspection and Repair ..................................... 6D-20 Armature ...................................................... 6D-20
Yoke............................................................. 6D-21
Brush and Brush Holder .............................. 6D-22
Overrunning Clutch...................................... 6D-22
Bearing ........................................................ 6D-23
Reassembly..................................................... 6D-24 Reassembly Steps ....................................... 6D-24
Important Operations ................................... 6D-25
Inspection After Assembly ........................... 6D-26
Magnetic Switch .............................................. 6D-27
Torque Specifications...................................... 6D-28

Pre-Heating System ........................................... 6D-29 Inspection and Repair ..................................... 6D-29 Visual Check................................................ 6D-29
Glow Relay .................................................. 6D-29
Glow Plug .................................................... 6D-29


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ENGINE ELECTRICAL (4JK1/4JJ1) 6D-5
Troubleshooting
Symptoms
• No charging
• Inadequate charging
• Excessive charging
• Unstable charging current
• Abnormal generator noise



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ENGINE DIAGNOSIS (C24SE) 6-1
SECTION 6
ENGINE DIAGNOSIS
TABLE OF CONTENTS
PAGE
Engine Diagnosis .............................................................................................................. 6- 2
Hard Starting ................................................................................................................. 6- 2
Engine Compression Test Procedure ......................................................................... 6- 3
Rough Engine Idling or Engine Stalling...................................................................... 6- 4
Rough Engine Running ................................................................................................ 6- 5
Hesitation ..................................................................................................................... . 6- 6
Engine Lacks Power ..................................................................................................... 6- 7
Engine Noisy ................................................................................................................. 6 - 8
Abnormal Noise Due to Hydraulic Lash Adjustor ...................................................... 6- 9
Troubleshooting Procedure ......................................................................................... 6- 9
Abnormal Combustion ................................................................................................. 6-11
Engine Oil Consumption Excessive............................................................................ 6-12
Fuel Consumption Excessive ...................................................................................... 6-13
Oil Problems.................................................................................................................. 6-13
Engine Oil Pressure Check .......................................................................................... 6-13
Malfunction Indicator Lamp ......................................................................................... 6-14


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6-4 ENGINE DIAGNOSIS (C24SE)
Rough Engine Idling or Engine Stalling
Condition Possible cause Correction
Trouble in fuel injection system Idle air control valve defective Replace
Throttle shutting off incomplete Correct or replace
Throttle position sensor circuit
open or shorted Correct or replace

Fuel injector circuits open or
shorted Correct or replace

Fuel injectors damaged Replace
Fuel pump relay defective Replace
Manifold Absolute Pressure
Sensor cable disconnected or
broken Correct or replace

Manifold Absolute Pressure
Sensor defective Replace

Engine Coolant Temperature
Sensor cable disconnected or
broken Correct or replace

Engine Coolant Temperature
Sensor defective Replace

Intake Air Temperature sensor
cable disconnected or broken Correct or replace

Intake Air Temperature sensor
defective Replace

Knock Sensor (KS) circuits open
or shorted Correct or replace
KS
defective Replace
KS Module circuits open or
ground Correct or replace

KS Module defective Replace
Vehicle Speed Sensor circuit open
or shorted Correct or replace

Vehicle Speed Sensor defective Replace
Trouble in emission control
system Engine Control Module defective Replace

Canister purge solenoid circuit
open Correct

Canister purge solenoid defective Replace
Evaporative Emission Canister
Purge control valve defective Replace

Trouble in ignition system Refer to Hard Start
Troubleshooting Guide
Others Engine lacks compression Refer to Hard Start
Troubleshooting Guide
Valve incorrectly seated Lap valve
Air Cleaner Filter clogged Replace filter element
Valve timing incorrect Readjust
Idle air control valve broken Replace


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ENGINE DIAGNOSIS (C24SE) 6-7
Engine Lacks Power
Condition Possible cause Correction
Trouble in fuel system Fuel Pressure Control Valve not
working normally Replace

Fuel injector clogged Clean or replace
Fuel pipe clogged Clean
Fuel filter clogged or fouled Replace
Fuel pump drive circuit not
working normally Correct or replace

Fuel tank not sufficiently breathing
due to clogged Evaporative
Emission Control System circuit Clean or replace

Water in fuel system Clean
Inferior quality fuel in fuel system Use fuel of specified octane rating
Engine Control Module supplied
poor voltage Correct circuit

Throttle Position Sensor cable
disconnected or broken Correct or replace

Throttle Position Sensor defective Replace
Manifold Absolute Pressure
Sensor not working normally Replace

Intake Air Temperature sensor not
working normally Replace

Engine Coolant Temperature
Sensor circuit open or shorted Correct or replace

Engine Coolant Temperature
Sensor defective Replace

Engine Control Module defective Replace
Trouble in intake or exhaust
system Air Cleaner Filter clogged Replace filter element

Air duct kicked or flattened Correct or replace
Ignition failure
- Refer to Hard Start
Troubleshooting Guide
Heat range of spark plug
inadequate Install spark plugs of adequate
heat range
Electronic Ignition System with
module Replace


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ENGINE DIAGNOSIS (C24SE) 6-9
Abnormal Noise Due to Hydraulic Lash Adjuster
Should abnormal noise due to the hydraulic lash
adjuster trouble be heard immediately after the engine
is started, inspect as follows:
Condition Possible cause Correction
Abnormal noise is heard Air contaminated Bleed
HLA is spongy Check ball valve broken Repair
Safety valve in cylinder head
broken Replace
Valve clearance is not zero HLA inside stick
Replace HLA assembly

Troubleshooting Procedure
Short out each spark plug in sequence using insulated
spark plug wire removers. Locate cylinder with
defective bearing by listening for abnormal noise that
stops when spark plug is shorted out.
Condition Possible cause Correction
Noise from connecting rods or
from connecting rod bearings
(Faulty connecting rods or
connecting rod bearings usually
make an abnormal noise slightly
higher than the crank bearing
noise, which becomes more
evident when engine is
accelerated) Bearing or crankshaft pin worn Replace connecting rod bearings
and crankshaft or regrind
crankshaft and install the under
size bearing
Crankpin out of round Replace connecting rod bearings
and crankshaft or regrind
crankshaft and install the under
size bearing
Connecting rod bent Correct or replace
Connecting rod bearing seized Replace connecting rod bearings
and crankshaft or regrind
crankshaft and install the under
size bearing

Troubleshooting Procedure
Abnormal noise stops when the spark plug on the
cylinder with defective parts is shorted out.
Condition Possible cause Correction
Piston and cylinder
(Faulty piston or cylinder usually
makes a combined mechanical
thumping noise which increases
when engine is suddenly
accelerated but diminishes
gradually as the engine warms up) Piston clearance increased due to
cylinder wear Replace piston and cylinder body

Piston seized Replace piston and cylinder body
Piston ring broken Replace piston and cylinder body
Piston defective Replace pistons and others


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6-10 ENGINE DIAGNOSIS (C24SE)
Troubleshooting Procedure
Condition Possible cause Correction
Piston pin noise
(Piston makes noise each time it
goes up and down) Piston pin or piston pin hole worn Replace piston, piston pin and
connecting rod assy

Troubleshooting Procedure
The slapping sound stops when spark plug on bad
cylinder is shorted out.
Condition Possible cause Correction
Timing belt noise Timing belt tension is incorrect Replace pusher or adjust the
tension pulley or replace timing
belt
Tensioner bearing defective Replace
Timing belt defective Replace
Timing wheels defective Replace
Timing belt comes in contact with
timing cover Replace timing belt and timing
cover
Valve noise Valve and valve guide seized Replace valve and valve guide
Valve spring broken Replace
Valve seat off-positioned Correct
Crankshaft noise Crankshaft end play excessive
(noise occurs when clutch is
engaged) Replace thrust bearing
Engine knocking
Preignition due to use of spark
plugs of inadequate heat range Install Spark Plugs of adequate
heat range
Fuel too low in octane rating Replace fuel
Wide Open Throttle enrichment
system failure Refer to Section 6E

Selection of transmission gear
incorrect Caution operator or incorrect gear
selection
Engine overheating Refer to "Engine Lacks Power"
Others Water pump defective Replace
V-belt slipping Adjust tension of V-belt or replace
V-belt


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ISUZU KB P190 2007