1998 ISUZU TROOPER Ecm

ENGINE MECHANICAL 6A – 71
12. Immediately install high pressure oil pipe and
tighten to specified torque.
Torque: 80 N·m (8.1 kg·m / 57.9 lb ft)
13. Install cylinder head noise insulator cover.
Refer to “Cylinder Head” in this manual.
14. Install intercooler assembly.
Refer to “Intercooler” in this manual.
15. Install air cleaner cover and air duct.
16. Use TECH2 to rewrite injector data to ECM.
For rewriting method refer to section “Data
Programming in Case of ECM Change” of 6E 4JX1
engine driveability and emissions in this manual.
NOTE:
1) On completion of servicing, bleed air from the
engine inside fuel passage by means of the priming
pump. (The priming pump should be operated more
times than in the case of conventional engines.)
2) As air is in the oil rail, it takes more time to start the
engine. Rough idling may occur while the air is
being bled completely after starting the engine, but
it does not indicate trouble.
The air will be bled and normal engine status will be
reached while the vehicle is driven for about 5 km
or engine is operated for about 5 minutes at 1500 to
2000 rpm.
3) The injector spare part will be provided for group
number B1, B2 and B3 only.

ENGINE FUEL 6C – 1
ENGINE FUEL
CONTENTS
GENERAL DESCRIPTION
General Description . . . . . . . . . . . . . . . . . . 6C–1
On-Vehicle Service . . . . . . . . . . . . . . . . . . 6C–7
Fuel Filter Assembly . . . . . . . . . . . . . . . . 6C–7
Fuel Filter Cartridge . . . . . . . . . . . . . . . . 6C–7
Injector . . . . . . . . . . . . . . . . . . . . . . . . . . 6C–9
Fuel Pump Pipe . . . . . . . . . . . . . . . . . . . 6C–13High Pressure Oil Pump . . . . . . . . . . . . . 6C–15
Fuel Tank . . . . . . . . . . . . . . . . . . . . . . . . 6C–20
Fuel Gauge Unit . . . . . . . . . . . . . . . . . . . 6C–21
Fuel Filler Cap . . . . . . . . . . . . . . . . . . . . 6C–21
To realize the compatibility between low exhaust
emission and high engine output, an HEUI
(Hydraulically actuated Electronically controlled Unit
Injector) system, has been introduced. This system is
comprised of a hydraulic system, fuel system, and
electronic control system, using a high-pressure oil
pump in place of the conventional fuel injection pump.
The oil pressurized by means of this pump and by
signals from the ECM (Electronic Control Module)
actuates the fuel injector provided for each cylinder.
Inside of the fuel injector, fuel pressure is increased due
to the high-pressure oil. The ECM detects the driving
state of the vehicle, forms, signals sent by engine and
other part sensors, which determines the optimum fuel
injection amount and timing, thus controlling the fuel
injectors. Thus high engine output, good fuel economy,
and low exhaust emission are realized.When working on the fuel system, there are several
things to keep in mind:
1) Any time the fuel system is being worked on,
disconnect the negative battery cable except for
those tests where battery voltage is required.
2) Always keep a dry chemical (Class B) fire
extinguisher near the work area.
3) Replace all pipes with the same pipe and fittings
that were removed.
Clean and inspect “O” rings. Replace where
required.
4) Always relieve the line pressure before servicing
any fuel system components.
5) Do not attempt repairs on the fuel system until you
have read the instructions and checked the pictures
relating to that repair.
6) After maintenance work, push priming pump and
send enough fuel to the fuel system before starting
the engine.
NOTE: In comparison with the conventional engine,
the capacity of fuel passage in the 4JX1 engine is
larger. It takes the priming pump more time to fill the
engine with fuel.

ENGINE FUEL 6C – 5
FUEL FILTER
Legend
(1) Priming Pump
(2) Fuel Filter Cartridge
A cartridge type fuel filter is used along with the piston
type fuel pump on the high pressure oil pump.
The fuel filter removes foreign material from the fuel
before it reaches the fuel pump.
A diaphragm type priming pump is installed at the top of
the fuel filter. It is used during the air bleeding
procedures.
INJECTOR ASSEMBLY
Legend
(1) Oil Passage
(2) Fuel Passage
1. Construction of Fuel Injector
The fuel injector is comprised of the solenoid
section, hydraulic line, and fuel line. Fuel injection is
controlled by the continuity time signal and
continuity start timing signal sent by the ECM
(Electronic Control Module) to the solenoid.
2. Working of Fuel Injector
1) The ECM detects the working of the engine from
its input signals, such as engine speed
accelerator throttle opening, and engine coolant
temperature, sending the optimal signals to the
solenoid.
1
2
041RW017
1
2
055RW018

6C – 6 ENGINE FUEL
2) With the current carried to the solenoid, a
poppet valve is opened by means of an
armature to let high-pressure engine oil into the
injector.
3) Under the oil pressure, the piston and plunger
are depressed to compress the fuel. The
pressure of the compressed fuel is increased
over the pressure of high-pressure engine oil by
the ratio (about 7 : 1) of piston top to plunger
bottom.
4) The injection nozzle end needle is lifted under
the increased pressure of the fuel for fuel
injection.
5) With current stopped from the ECM, the poppet
valve is closed which holds up the high-pressure
engine oil and lets the oil used to compress fuel
out of the injector through its drain hole.

ENGINE FUEL 6C – 11
8. Install injector harness assembly, reconnect
harness connecter to injector.
9. Record the identification marking of injector for
each cylinder that is indicated on the upper portion
of injector.
Legend
(1) Part Number
(2) Category Number (Grade code)
(3) Serial Number
(4) Bar Code
10. Install cylinder head assembly.
Refer to “Cylinder Head” in this manual.
11. Fill with about 300cc of engine oil from the high
pressure oil pipe installation port of the oil rail using
an oil filler.
If assembled without filling the oil rail with oil, the
time for engine starting will be longer.
12. Immediately install high pressure oil pipe and
tighten to specified torque.
Torque: 80 N·m (8.1 kg·m / 57.9 lb ft)
13. Install cylinder head noise insulator cover.
Refer to “Cylinder Head” in this manual.
14. Install intercooler assembly.
Refer to “Intercooler” in this manual.
15. Install air cleaner cover and air duct.
16. Use TECH2 to rewrite injector data to ECM.
For rewriting method refer to section “Data
Programming in Case of ECM Change” of section
6E 4JX1 engine driveability and emissions in this
manual.NOTE:
1) On completion of servicing, bleed air from the
engine inside fuel passage by means of the priming
pump. (The priming pump should be operated more
times than in the case of conventional engines.)
2) As air is in the oil rail, it takes more time to start the
engine. Rough idling may occur while the air is
being bled completely after engine start, but it does
not indicate trouble.
The air will be bled and normal engine status will be
reached while the vehicle is driven for about 5 km
or engine is operated for about 5 minutes at 1500 to
2000 rpm.
3) The injector spare part will be provided for group
number B1, B2 and B3 only.
Injector Grade code Programming
(Injector Change)
In case of an injector change, the injector grade code
(category number) must be programmed by Tech-2.
Programming Procedure
1. Connect the Tech-2 to the vehicle DLC.
2. Turn the starter switch to the “ON” position.
3. Select the “Diagnosis” from the Main menu.
4. Select the “Programming” from the Application
menu.
1
4
32
055RW00001
F0 : %JBHOPTUJD
$PEF
F1 : %BUB
%JTQMBZ
F2 : 4OBQTIPU
F3 : .JTDFMMBOFPVT
5FTU
F4 : 1SPHSBNNJOH"QQMJDBUJPO
.FOV
035RW00002

ENGINE ELECTRICAL 6D – 23
QOS4 PREHEATING SYSTEM
GENERAL DESCRIPTION
QOS4 preheating system features a quick-on glow plug
with thermometer control of the glowing time and the
afterglow time function.
The system consists of the ECM, indicator lamp, ECT
sensor, vehicle speed sensor, relay and temperature
self-control type glow plugs.With the employment of the ECT sensor, the glow time
changes according to the engine coolant temperature,
thus allowing optimum starting conditions to be
obtained.
The after glow time function is controlled by ECM.
NOTE:
Refer to DTC P0380 and P0381 of 6E section.
SYSTEM DIAGRAM
+
-KEY
50A
ECM
50A
GLOW
50A
2
WHT/
RED
0.5
BLK/
BLU
ECM J1-15 3
WHT/
RED
3
RED/
BLKMAIN
80A
8BLK/RED
Glow
Relay
GLOW PLUG 4
BATTHeater & A/C
Relay
060RW132

6D – 24 ENGINE ELECTRICAL
1 Inspection on Quick Heating Operation
1. Disconnect ECT-sensor connection on the
thermostat housing
Legend
(1) ECT Sensor
(2) EVRV
2. Connect the circuit tester between glow plug and
engine earth.
3. Inspect the following items with starter switch set to
ON position (but do not start the engine).
1) The glow indicator shall light for about 5 sec.
2) The circuit tester shall indicate power supply
voltage for 180 sec.
If above specifications are not satisfied, inspect
wire harness, glow relay and ECT-sensor. If
satisfied, inspect glow plug.2 Inspection on Afterglow Operation
1. Disconnect ECT-sensor connection on the
thermostat housing
Legend
(1) ECT Sensor
(2) EVRV
2. Connect the circuit tester between glow plug and
engine earth.
3. Inspect the following item with the engine started.
1) The circuit tester shall indicate about 12 volts
after 180 seconds of engine start.
•If above specifications are not satisfied, inspect
battery voltage, engine earth, wiring harness,
glow plug, and ECM.
12
060RW166
065RW035
12
060RW166
065RW035
INSPECTION ON QOS4 SYSTEM OPERATION

6E±1 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
4JX1±TC 3.0L ENGINE
DRIVEABILITY AND EMISSIONS
CONTENTS
Specification 6E±7. . . . . . . . . . . . . . . . . . . . . . . . . .
Tightening Specifications 6E±7. . . . . . . . . . . . . . .
Diagrams and Schematics 6E±8. . . . . . . . . . . . . . . .
ECM Wiring Diagram (1 of 6) 6E±8. . . . . . . . . . . .
ECM Wiring Diagram (2 of 6) 6E±9. . . . . . . . . . . .
ECM Wiring Diagram (3 of 6) 6E±10. . . . . . . . . . . .
ECM Wiring Diagram (4 of 6) 6E±11. . . . . . . . . . . .
ECM Wiring Diagram (5 of 6) 6E±12. . . . . . . . . . . .
ECM Wiring Diagram (6 of 6) 6E±13. . . . . . . . . . . .
ECM Pinouts 6E±14. . . . . . . . . . . . . . . . . . . . . . . . . . .
ECM Pinout Table, 32-Way Connector ± J1
RED ± Upper 6E±14. . . . . . . . . . . . . . . . . . . . . . . . .
ECM Pinout Table, 32-Way Connector ± J1
RED ± Lower 6E±15. . . . . . . . . . . . . . . . . . . . . . . . .
ECM Pinout Table, 32-Way Connector ± J2
BLUE ± Upper 6E±16. . . . . . . . . . . . . . . . . . . . . . . .
ECM Pinout Table, 32-Way Connector ± J2
BLUE ± Lower 6E±17. . . . . . . . . . . . . . . . . . . . . . . .
ECM Pinout Table, 5-Way Connector ± J3 6E±18
Component Locator 6E±19. . . . . . . . . . . . . . . . . . . . .
Sensors and Miscellaneous Component
Locators 6E±21. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Abbreviations Charts 6E±23. . . . . . . . . . . . . . . . . . . .
Diagnosis 6E±24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Strategy-Based Diagnostics 6E±24. . . . . . . . . . . . .
Strategy-Based Diagnostics 6E±24. . . . . . . . . . . . .
DTC Stored 6E±24. . . . . . . . . . . . . . . . . . . . . . . . . . .
No DTC 6E±24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
No Matching Symptom 6E±24. . . . . . . . . . . . . . . . .
Intermittents 6E±24. . . . . . . . . . . . . . . . . . . . . . . . . .
No Trouble Found 6E±24. . . . . . . . . . . . . . . . . . . . .
Verifying Vehicle Repair 6E±24. . . . . . . . . . . . . . . .
General Service Information 6E±25. . . . . . . . . . . . . .
Serviceability Issues 6E±25. . . . . . . . . . . . . . . . . . .
Visual/Physical Engine Compartment
Inspection 6E±25. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Basic Knowledge of Tools Required 6E±25. . . . . .
Serial Data Communications 6E±25. . . . . . . . . . . . . .
Class II Serial Data Communications 6E±25. . . . .
On-Board Diagnostic (OBD) 6E±25. . . . . . . . . . . . . .
On-Board Diagnostic Tests 6E±25. . . . . . . . . . . . .
Comprehensive Component Monitor
Diagnostic Operation 6E±25. . . . . . . . . . . . . . . . . .
Common OBD Terms 6E±26. . . . . . . . . . . . . . . . . .
The Diagnostic Executive 6E±26. . . . . . . . . . . . . . .
DTC Types 6E±26. . . . . . . . . . . . . . . . . . . . . . . . . . .
Verifying Vehicle Repair 6E±27. . . . . . . . . . . . . . . . Reading Flash Diagnostic Trouble Codes 6E±27.
Reading Diagnostic Trouble Codes Using
a TECH 2 6E±28. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tech 2 Scan Tool 6E±29. . . . . . . . . . . . . . . . . . . . . .
Getting Started 6E±30. . . . . . . . . . . . . . . . . . . . . . . .
DTC Modes 6E±32. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC Information Mode 6E±32. . . . . . . . . . . . . . . . .
Injector Test 6E±32. . . . . . . . . . . . . . . . . . . . . . . . . .
EGR Valve Test 6E±32. . . . . . . . . . . . . . . . . . . . . . .
Rail Pressure Control Valve Test 6E±32. . . . . . . . .
Injector Balance Test 6E±32. . . . . . . . . . . . . . . . . . .
Data Programming in Case of ECM Change 6E±32
Rail Pressure Sensor Programming 6E±33. . . . . .
Injector Group Sign Programming
(Injector Change) 6E±33. . . . . . . . . . . . . . . . . . . . .
On-Board Diagnostic (OBD) System Check 6E±35.
Circuit Description 6E±37. . . . . . . . . . . . . . . . . . . . .
Diagnostic Aids 6E±37. . . . . . . . . . . . . . . . . . . . . . . .
Engine Control Module ECM Diagnosis 6E±39. . . .
Multiple ECM Information Sensor DTCS Set 6E±39
Circuit Description 6E±39. . . . . . . . . . . . . . . . . . . . .
Diagnostic Aids 6E±39. . . . . . . . . . . . . . . . . . . . . . . .
EGR (Exhaust Gas Recirculation) Diagnosis 6E±41
Tech 2 Data Definitions and Ranges 6E±41. . . . . . .
Typical Scan Data Values 6E±41. . . . . . . . . . . . . . . .
Test Conditions 6E±41. . . . . . . . . . . . . . . . . . . . . . . .
4JX1-TC Engine (Automatic and Manual
Transmission) 6E±42. . . . . . . . . . . . . . . . . . . . . . . .
No Malfunction Indicator Lamp (MIL) 6E±44. . . . . . .
Circuit Description 6E±44. . . . . . . . . . . . . . . . . . . . .
Diagnostic Aids 6E±44. . . . . . . . . . . . . . . . . . . . . . . .
Malfunction Indicator Lamp (MIL) ªONº
Steady 6E±47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Circuit description 6E±47. . . . . . . . . . . . . . . . . . . . .
Diagnostic Aids 6E±47. . . . . . . . . . . . . . . . . . . . . . . .
Engine Cranks But Will Not Run 6E±49. . . . . . . . . . .
Circuit Description 6E±49. . . . . . . . . . . . . . . . . . . . .
Diagnostic Aids 6E±49. . . . . . . . . . . . . . . . . . . . . . . .
Exhaust Gas Recirculation (EGR) System
Check 6E±52. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Circuit Description 6E±52. . . . . . . . . . . . . . . . . . . . .
ECM Diagnostic Trouble Codes 6E±54. . . . . . . . . . .
ECM Diagnostic Trouble Codes 6E±54. . . . . . . . .
Diagnostic Trouble Code (DTC) P0107
(Flash DTC 34)
MAP Sensor Circuit Low Voltage 6E±56. . . . . . . . . .