2004 ISUZU TF SERIES content

FUEL SYSTEM 6C – 1


SECTION 6C
FUEL SYSTEM


TABLE OF CONTENTS
PAGE
Main Data and Specifications ....................................................................................... 6C - 3
General Description....................................................................................................... 6C - 4
Fuel Flow .................................................................................................................... 6C - 4
Fuel Filter and Water Separator ............................................................................... 6C - 5
Injection Pump ........................................................................................................... 6C - 7
Injection Nozzle ......................................................................................................... 6C - 8
Fuel Tank ........................................................................................................................ 6C - 9
Removal ..................................................................................................................... 6C - 9
Installation ................................................................................................................. 6C - 10
Fuel Pump ...................................................................................................................... 6C - 12
Removal...................................................................................................................... 6C - 13
Installation.................................................................................................................. 6C - 13
Fuel Tube / Quick - Connector Fittings ........................................................................ 6C - 14
Filler Neck ...................................................................................................................... 6C - 16
Removal...................................................................................................................... 6C - 16
Installation.................................................................................................................. 6C - 16
Fuel Filler Cap ................................................................................................................ 6C - 17
Injection Pump ............................................................................................................... 6C - 18
Removal and Installation .......................................................................................... 6C - 18
Removal...................................................................................................................... 6C - 18
Installation.................................................................................................................. 6C - 21

ENGINE ELECTRICAL 6D – 1


SECTION 6D
ENGINE ELECTRICAL


TABLE OF CONTENTS
PAGE
Main Data and Specifications ......................................................................................... 6D - 2
General Description......................................................................................................... 6D - 3
Torque Specifications ..................................................................................................... 6D - 5
Generator.......................................................................................................................... 6D - 7
Removal and Installation ............................................................................................ 6D - 7
Disassembly................................................................................................................. 6D - 9
Inspection and Repair ................................................................................................. 6D - 12
Reassembly.................................................................................................................. 6D - 18
Starter Motor .................................................................................................................... 6D - 22
Removal and Installation ............................................................................................ 6D - 22
Disassembly................................................................................................................. 6D - 23
Inspection and Repair ................................................................................................. 6D - 26
Reassembly.................................................................................................................. 6D - 29
Pre-heating System ......................................................................................................... 6D -33
Inspection and Repair ................................................................................................. 6D -33
Glow Relay ................................................................................................................... 6D -33
Glow Plug ..................................................................................................................... 6D -33
EGR System ................................................................................................................. 6D -33

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–1
ENGINE
CONTENTS
4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
ABBREVIATION CHARTS ........................ 6E-9
4JA1-TC .................................................... 6E-10
4JH1-TC .................................................... 6E-11
ECM CIRCUIT DIAGRAM (4JA1-TC) ........ 6E-14
ECM CIRCUIT DIAGRAM (4JA1-TC) ........ 6E-15
ECM CIRCUIT DIAGRAM (4JH1-TC) ........ 6E-16
ECM CIRCUIT DIAGRAM (4JH1-TC) ........ 6E-17
GROUND POINT CHART GENERAL EXPORT
(LHD) (1/4) ............................................... 6E-18
LOCATION ................................................ 6E-34
PARTS LOCATION ................................... 6E-39
CONNECTOR LIST ................................... 6E-40
RELAY AND FUSE .................................... 6E-43
RELAY AND FUSE BOX LOCATION
(LHD & RHD) ........................................... 6E-43
RELAY AND FUSE BOX LOCATION
(LHD & RHD) ........................................... 6E-44
FUSE AND RELAY LOCATION (LHD & RHD) 6E-45
ECM WIRING DIAGRAM (1/7) .................. 6E-46
ECM WIRING DIAGRAM (2/7) .................. 6E-47
ECM WIRING DIAGRAM (3/7) .................. 6E-48
ECM WIRING DIAGRAM (4/7) .................. 6E-49
ECM WIRING DIAGRAM (5/7) .................. 6E-50
ECM WIRING DIAGRAM (6/7) .................. 6E-51
ECM WIRING DIAGRAM (7/7) .................. 6E-52
ECM CONNECTOR PIN ASSIGNMENT &
OUTPUT SIGNAL .................................... 6E-53
GENERAL DESCRIPTION FOR ECM AND
SENSORS ............................................... 6E-64
Engine Control Module (ECM) ................... 6E-64
Pump Control Unit (PSG) & Data Ex change
Between Control Module ......................... 6E-64
Mass Air Flow (MAF) Sensor & Intake Air
Temperature (IAT) Sensor ....................... 6E-65
Throttle Position Sensor (TPS) .................. 6E-66
Crankshaft Position (CKP) Sensor ............ 6E-66
Engine Coolant Temperature (ECT) Sensor 6E-67
Vehicle Speed Sensor (VSS) .................... 6E-67
GENERAL DESCRIPTION FOR EGR
(EXHAUST GAS RE-CIRCULATION) ..... 6E-68
GENERAL DESCRIPTION FOR
INJECTION PUMP .................................. 6E-70Outline ....................................................... 6E-70
Cross-section View .................................... 6E-70
Low Pressure Fuel Circuit .......................... 6E-71
High Pressure Fuel Circuit ......................... 6E-72
Pump Camshaft Speed Sensor ................. 6E-72
High Pressure Solenoid Valve ................... 6E-73
Timing Control Valve (TCV) ....................... 6E-74
ISUZU Strategy Based Diagnostics .............. 6E-76
Overview .................................................... 6E-76
STRATEGY BASED DIAGNOSTICS CHART 6E-76
Diagnostic Thought Process ...................... 6E-77
1. Verify the Complaint .............................. 6E-77
2. Perform Preliminary Checks .................. 6E-77
3. Check Bulletins and Troubleshooting Hints 6E-78
4. Perform Service Manual Diagnostic Checks 6E-78
5a and 5b. Perform Service Manual Diagnostic
Procedures .............................................. 6E-78
5c. Technician Self Diagnoses .................. 6E-78
5d. Intermittent Diagnosis .......................... 6E-79
5e. Vehicle Operates as Designed ............ 6E-80
6. Re-examine the complaint ..................... 6E-81
7. Repair and Verify Fix ............................. 6E-81
GENERAL SERVICE INFORMATION ....... 6E-82
ON-BOARD DIAGNOSTIC (OBD) ............. 6E-82
TECH 2 OPERATING FLOW CART
(START UP) ............................................. 6E-86
TYPICAL SCAN DATA & DEFINITIONS
(ENGINE DATA) ................................... 6E-88
TYPICAL SCAN DATA & DEFINITIONS
(ENGINE DATA) ................................... 6E-90
MISCELLANEOUS TEST .......................... 6E-92
Plotting Snapshot Graph ............................ 6E-93
Plotting Graph Flow Chart (Plotting graph
after obtaining vehicle information) .......... 6E-94
Flow Chart for Snapshot Replay
(Plotting Graph) ....................................... 6E-95
SNAPSHOT DISPLAY WITH TIS2000 ...... 6E-96
ON-BOARD DIAGNOSTIC (OBD) SYSTEM
CHECK .................................................... 6E-105
Circuit Description ...................................... 6E-105
Diagnostic Aids .......................................... 6E-105
Test Description ......................................... 6E-105

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–361
SYMPTOM DIAGNOSIS
PRELIMINARY CHECKS
Before using this section, perform the “On-Board
Diagnostic (OBD) System Check” and verify all of the
following items:
The engine control module (ECM) and check engine
lamp (MIL=malfunction indicator lamp are operating
correctly.
There are no Diagnostic Trouble Code(s) stored.
Tech 2 data is within normal operating range. Refer to
Typical Scan Data Values.
Verify the customer complaint and locate the correct
symptom in the table of contents. Perform the
procedure included in the symptom chart.
VISUAL/PHYSICAL CHECK
Several of the symptom procedures call for a careful
visual/physical check. This can lead to correcting a
problem without further checks and can save valuable
time. This check should include the following items:
ECM grounds for cleanliness, tightness and proper
location.
Vacuum hoses for splits, kinks, and proper
connection. Check thoroughly for any type of leak or
restriction.
Air intake ducts for collapsed or damaged areas.
Air leaks at throttle body mounting area, mass air flow
(MAF) sensor and intake manifold sealing surfaces.
Wiring for proper connections, pinches and cuts.
INTERMITTENT
Important: An intermittent problem may or may not turn
on the check engine lamp (MIL=malfunction indicator
lamp) or store a Diagnostic Trouble Code. Do NOT use
the Diagnostic Trouble Code (DTC) charts for
intermittent problems.
The fault must be present to locate the problem.
Most intermittent problems are cased by faulty electrical
connections or wiring. Perform a careful visual/physical
check for the following conditions.
Poor mating of the connector halves or a terminal not
fully seated in the connector (backed out).
Improperly formed or damaged terminal.
All connector terminals in the problem circuit should
be carefully checked for proper contact tension.
Poor terminal-to-wire connection. This requires
removing the terminal form the connector body to
check.
Check engine lamp (MIL=malfunction indicator lamp)
wire to ECM shorted to ground.
Poor ECM grounds. Refer to the ECM wiring
diagrams.Road test the vehicle with a Digital Multimeter
connected to a suspected circuit. An abnormal voltage
when the malfunction occurs is a good indication that
there is a fault in the circuit being monitored.
Using Tech 2 to help detect intermittent conditions. The
Tech 2 have several features that can be used to
located an intermittent condition. Use the following
features to find intermittent faults:
To check for loss of diagnostic code memory,
disconnect the MAF sensor and idle the engine until the
check engine lamp (MIL=malfunction indicator lamp)
comes on. Diagnostic Trouble Code P0100 should be
stored and kept in memory when the ignition is turned
OFF.
If not, the ECM is faulty. When this test is completed,
make sure that you clear the Diagnostic Trouble Code
P0100 from memory.
An intermittent check engine lamp (MIL=malfunction
indicator lamp) with no stored Diagnostic Trouble Code
may be caused by the following:
Check engine lamp (MIL=malfunction indicator lamp)
wire to ECM short to ground.
Poor ECM grounds. Refer to the ECM wiring
diagrams.
Check for improper installation of electrical options such
as light, cellular phones, etc. Check all wires from ECM
to the ignition control module for poor connections.
Check for an open diode across the A/C compressor
clutch and check for other open diodes (refer to wiring
diagrams in Electrical Diagnosis).
If problem has not been found, refer to ECM connector
symptom tables.
Check the “Broadcast Code” of the ECM, and
compare it with the latest Isuzu service bulletins and/
or Isuzu EEPROM reprogramming equipment to
determine if an update to the ECM's reprogrammable
memory has been released.
This identifies the contents of the reprogrammable
software and calibration contained in the ECM.
If the “Broadcast Code” is not the most current
available, it is advisable to reprogram the ECM's
EEPROM memory, which may either help identify a
hard-to find problem or may fix the problem.
The Service Programming System (SPS) will not allow
incorrect software programming or incorrect calibration
changes.

EXHAUST SYSTEM 6F – 1


SECTION 6F
EXHAUST SYSTEM
TABLE OF CONTENTS
PAGE
Main Data and Specifications ........................................................................................... 6F - 2
General Description........................................................................................................... 6F - 3
Removal and Installation................................................................................................... 6F - 4
Inspection and Repair ....................................................................................................... 6F - 6
General Description........................................................................................................... 6F -7
EGR System Diagram ........................................................................................................ 6F 9
Inspection ........................................................................................................................... 6F-11
EGR Cooler (4JA1TC/4JH1TC Euro-III model) ................................................................. 6F-12
Turbocharger ..................................................................................................................... 6F -15
Main Data and Specifications ....................................................................................... 6F -15
General Description........................................................................................................... 6F -16
Inspection and Repair ....................................................................................................... 6F -17
Special Tools...................................................................................................................... 6F -19
IHI Service Network ........................................................................................................... 6F -20

ACCELERATOR CONTROL 6H – 1


SECTION 6H
ACCELERATOR CONTROL


TABLE OF CONTENTS
PAGE
Removal and Installation............................................................................................... 6H - 2
Removal...................................................................................................................... 6H - 6
Inspection................................................................................................................... 6H - 6
Installation.................................................................................................................. 6H - 6

ENGINE MECHANICAL (6VE1 3.5L) 6A-1
ENGINE
CONTENTS
Engine Mechanical.................................................6A
Engine Cooling........................................................6B
Engine Fuel.............................................................6C
Engine Electrical.....................................................6D1
Ignition System.......................................................6D2
Starting and Changing System.............................6D3 Driveability and Emissions.....................................6E
Engine Exhaust.......................................................6F
Engine Lubrication..................................................6G
Engine Speed Control System..............................6H
Induction...................................................................6J


ENGINE MECHANICAL (6VE1 3.5L)
CONTENTS

Service Precaution................................................. 6A-2
General Description............................................... 6A-3
Engine Diagnosis.................................................... 6A-4
Cylinder Head Cover LH........................................ 6A-21
Removal............................................................... 6A-21
Installation............................................................ 6A-21
Cylinder Head Cover RH....................................... 6A-23
Removal............................................................... 6A-23
Installation............................................................ 6A-23
Common Chamber................................................. 6A-24
Removal............................................................... 6A-24
Installation............................................................ 6A-25
Exhaust Manifold LH.............................................. 6A-26
Removal............................................................... 6A-26
Installation............................................................ 6A-26
Exhaust Manifold RH............................................. 6A-27
Removal............................................................... 6A-27
Installation............................................................ 6A-27
Crankshaft Pulley................................................... 6A-28
Removal............................................................... 6A-28
Installation............................................................ 6A-28
Timing Belt.............................................................. 6A-29
Removal............................................................... 6A-29
Installation............................................................ 6A-30
Camshaft................................................................. 6A-34
Removal............................................................... 6A-34
Installation............................................................ 6A-34
Cylinder Head......................................................... 6A-37
Removal............................................................... 6A-37
Installation............................................................ 6A-37
Valve Stem Oil Controller , Valve Spring
and Valve Guide.................................................... 6A-39
Removal................................................................ 6A-39
Installation............................................................. 6A-39
Piston, Piston Ring and Connecting Rod............ 6A-40
Removal................................................................ 6A-40
Installation............................................................. 6A-41
Crankshaft and Main Bearings.............................. 6A-43
Removal................................................................ 6A-43
Installation............................................................. 6A-44
Rear Oil Seal........................................................... 6A-48
Removal................................................................ 6A-48
Installation............................................................. 6A-48
Engine Assembly.................................................... 6A-49
Removal................................................................ 6A-49
Installation............................................................. 6A-49
Cylinder Head.......................................................... 6A-52
Cylinder Head and Associated Parts................ 6A-52
Disassembly......................................................... 6A-53
Clean..................................................................... 6A-53
Inspection and Repair......................................... 6A-53
Reassembly.......................................................... 6A-54
Valve Spring, Oil Controller, Valve, Valve
Guide....................................................................... 6A-56
Valve Spring, Oil Controller, Valve, Valve
Guide and Associated Parts............................. 6A-56
Disassembly......................................................... 6A-57
Inspection and Repair......................................... 6A-57
Reassembly.......................................................... 6A-61
Camshaft.................................................................. 6A-64
Camshaft and Associated Parts........................ 6A-64
Disassembly......................................................... 6A-64
Inspection and Repair......................................... 6A-65
Reassembly.......................................................... 6A-67

ENGINE COOLING (6VE1 3.5L) 6B-1
ENGINE
ENGINE COOLING (6VE1 3.5L)
CONTENTS

Service Precaution............................................. 6B–1
General Description ........................................... 6B–2
Diagnosis ........................................................... 6B–5
Draining and Refilling Cooling System .............. 6B–6
Water Pump ...................................................... 6B–7
Water Pump and Associated Parts ................ 6B–7
Removal ......................................................... 6B–7
Inspection ....................................................... 6B–7
Installation....................................................... 6B–7
Thermostat ........................................................ 6B–9
Thermostat and Associated Parts .................. 6B–9
Removal ......................................................... 6B–9
Inspection ....................................................... 6B–9

Installation ...................................................... 6B–9
Radiator ............................................................. 6B–10
Radiator and Associated Parts ....................... 6B–10
Removal ......................................................... 6B–11
Inspection ....................................................... 6B–11
Installation ...................................................... 6B–12
Drive Belt and Cooling Fan ................................ 6B–15
Drive Belt and Associated Parts ..................... 6B–15
Inspection ....................................................... 6B–15
Installation ...................................................... 6B–15
Main Data and Specifications ............................ 6B–16
Special Tool .................................................... 6B–18


Service Precaution
WARNING: THIS VEHICLE HAS A SUPPLEMENTAL
RESTRAINT SYSTEM (SRS). REFER TO THE SRS
COMPONENT AND WIRING LOCATION VIEW IN
ORDER TO DETERMINE WHETHER YOU ARE
PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING. WHEN YOU
ARE PERFORMING SERVICE ON OR NEAR THE
SRS COMPONENTS OR THE SRS WIRING, REFE
R
TO THE SRS SERVICE INFORMATION. FAILURE TO
FOLLOW WARNINGS COULD RESULT IN
POSSIBLE AIR BAG DEPLOYMENT, PERSONAL
INJURY, OR OTHERWISE UNNEEDED SRS SYSTEM
REPAIRS.

CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, o
r
other corrosion inhibitors) on threaded fasteners or
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener.
When you install fasteners, use the correct
tightening sequence and specifications. Following
these instructions can help you avoid damage to
parts and systems.