1998 ISUZU TROOPER fuel filter

6A – 10 ENGINE MECHANICAL
8. Check the engine oil level and replenish to the
specified level if required.
9. Start the engine and check for oil leakage from the
main oil filter.
FUEL SYSTEM
Fuel filter
Replacement Procedure
1. Loosen the used fuel filter by turning it
counterclockwise with the filter wrench.
Filter Wrench : 5-8840-0203-0
2. Clean the filter cover fitting faces.
This will allow the new fuel filter to seat properly.
3. Apply a light coat of engine oil to the O-ring.
4. Turn the fuel filter until the sealing face comes in
contact with the O-ring.
5. Turn the fuel filter with a filter wrench 2/3 of a turn
until sealed.
Filter Wrench: 5-8840-0203-0Legend
(1) Priming pump
6. Operate the priming pump until the air is discharged
completely from fuel system.
NOTE: The use of an Isuzu genuine fuel filter is
strongly recommended.
COOLING SYSTEM
Coolant Level
Check the coolant level and replenish the radiator
reserve tank as necessary.
If the coolant level falls below the “‘MIN” line, carefully
check the cooling system for leakage. Then add
enough coolant to bring the level up to the “MAX” line.
NOTE: Do not overfill the reserve tank.
012RW112
012RW078
1
012RW111
012RW080

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.

6C – 2 ENGINE FUEL
FUEL FLOW
1
14 Except above region
89
10111
2
2
4
12
5 6
7
3
13
14 For Europe, Nicaragua,
Argentina, Philippin
11
4
Legend
(1) Fuel Filler Cap
(2) Fuel Tank
(3) Rollover Valve
(4) Fuel Supply Pipe
(5) Fuel Filter with Priming Pump
(6) Fuel Pump
(7) High Pressure Oil Pump(8) Cylinder Head
(9) Injector
(10) Orifice
(11) Fuel Return Pipe
(12) Fuel Tank Pressure Release Hose
(13) Intake Air Duct
(14) Fuel Tank Pressure Control Valve
040R200001

6C – 4 ENGINE FUEL
HIGH PRESSURE OIL PUMP, OIL FLOW
1
33
32
31
30
1
2
3
4
56
8
97
10
11
12
13
14 23 29
25
28
27262415
16
17 18
19 20 21 22
Legend
(1) Camshaft
(2) Balance Shaft
(3) Crankshaft
(4) Oil Cooler and Oil Filter Assembly
(5) Oil Filter Relief Valve 98Kpa (1 kg/cm
2/14.2 Psi)
(6) Oil Cooler Relief Valve 245 Kpa (2.5 kg/cm2/
36 Psi)
(7) First Oil Pump
(8) Main Oil Relief Valve 588 Kpa (6 kg/cm
2/ 85 Psi)
(9) To Oil Pan
(10) To Oil Pan
(11) Injector
(12) Oil Rail
(13) Sub Oil Filter Relief Valve 98Kpa (1 kg/cm
2/
14.2 Psi)
(14) Sub Oil Filter
(15) Relief Valve 588 Kpa (6 kg/cm
2/ 85 Psi)
(16) Second Oil Pump(17) Oil Pan
(18) To Oil Pan
(19) Balance Shaft
(20) Cooling Jet Relief Valve 245 Kpa (2.5 kg/cm
2/
36 Psi)
(21) Cooling Jet
(22) To Oil Pan
(23) Two Way Check Valve
(24) Nipple Filter
(25) Edge Filter
(26) Edge Filter
(27) High Pressure Oil Pump Assembly
(28) To Oil Pan
(29) Pressure Control Valve
(30) To Oil Pan
(31) Turbocharger
(32) Oil Gallery
(33) Timing Gear Train
040RW018

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

ENGINE FUEL 6C – 7
ON-VEHICLE SERVICE
FUEL FILTER ASSEMBLY
REMOVAL
1. Disconnect battery ground cable.
2. Fuel Filler cap
3. Fuel Hose
1) Disconnect fuel hose from filter body.
Plug the hose ends to prevent fuel spillage.
4. Remove the Bolt on Fuel Filter Bracket
5. Remove Fuel Filter Assembly
INSTALLATION
1. Install the fuel filter assembly
2. Tighten the Fuel Filter Bracket Fixing Bolt
3. Fuel Hose
1) Connect hoses to filter body.
4. Fuel Filler Cap
1) Connect the battery ground cable.
2) Feed fuel to the fuel pump by priming, and bleed
the air from fuel system.
FUEL FILTER CARTRIDGE
DISASSEMBLY
1. Drain fuel completely from the fuel filter.
2. Protect the filter body with cloth and lightly grip with
a vise.
3. Remove the cartridge using a filter wrench.
Filter wrench: 5-8840-0203-0
1
Legend
(1) Priming Pump
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6C – 8 ENGINE FUEL
REASSEMBLY
1. Clean the cartridge mounting surface of the filter
body so that the cartridge can be secured.
Apply engine oil thinly to new cartridge O-ring.
2. To facilitate bleeding, fill the new cartridge with light
oil.
3. Tighten the cartridge until O-ring comes in contact
with the seal, taking care not to spill the light oil.
4. Retighten 1/3 – 2/3 using a filter wrench.
Filter wrench: 5-8840-0203-0
Bleeding
1. Loosen air bleeding plug.
2. Operate priming pump to bleed the air in the fuel
line.
3. Operate the priming pump until the fuel is overflow
from air bleeding plug.
4. Tighten the air bleeding plug.
5. Start the engine, and if it is not started in 10
seconds or less, repeat the bleeding steps.
6. Make sure of no fuel leakage, and tighten the
priming pump.
Legend
(1) Priming Pump
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.
012RW078
1
012RW111

6E±6
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Removal Procedure 6E±212. . . . . . . . . . . . . . . . . . . .
Installation Procedure 6E±212. . . . . . . . . . . . . . . . . .
Fuel Filter Cap 6E±213. . . . . . . . . . . . . . . . . . . . . . . . . .
General Description 6E±213. . . . . . . . . . . . . . . . . . . .
Inspection Procedure 6E±213. . . . . . . . . . . . . . . . . .
Fuel Filter 6E±213. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal and Installation Procedure 6E±213. . . . . .
Fuel Gauge Unit 6E±213. . . . . . . . . . . . . . . . . . . . . . . .
Removal Procedure 6E±213. . . . . . . . . . . . . . . . . . . .
Installation Procedure 6E±214. . . . . . . . . . . . . . . . . .
Fuel Injectors 6E±214. . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal and Installation Procedure 6E±214. . . . . .
Fuel Temperature Sensor 6E±214. . . . . . . . . . . . . . . .
Removal Procedure 6E±214. . . . . . . . . . . . . . . . . . . .
Installation Procedure 6E±215. . . . . . . . . . . . . . . . . .
Rail Pressure (RP) Sensor 6E±216. . . . . . . . . . . . . . .
Removal Procedure 6E±216. . . . . . . . . . . . . . . . . . . .
Installation Procedure 6E±216. . . . . . . . . . . . . . . . . .
Fuel Tank 6E±216. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal Procedure 6E±216. . . . . . . . . . . . . . . . . . . .
Throttle Body (TB) 6E±217. . . . . . . . . . . . . . . . . . . . . . .
Removal Procedure 6E±217. . . . . . . . . . . . . . . . . . . .
Installation Procedure 6E±217. . . . . . . . . . . . . . . . . .
Air Conditioning (A/C) Relay 6E±217. . . . . . . . . . . . . .
Removal Procedure 6E±217. . . . . . . . . . . . . . . . . . . .
Installation Procedure 6E±217. . . . . . . . . . . . . . . . . .
Exhaust Gas Recirculation (EGR) Vacuum
Switch Valve (VSV) 6E±217. . . . . . . . . . . . . . . . . . . . .
Removal Procedure 6E±217. . . . . . . . . . . . . . . . . . . .
Installation Procedure 6E±218. . . . . . . . . . . . . . . . . .
Electronic Vacuum Regurating Valve (EVRV) 6E±219
Removal Procedure 6E±219. . . . . . . . . . . . . . . . . . . .
Installation Procedure 6E±220. . . . . . . . . . . . . . . . . .
Wiring and Connectors 6E±220. . . . . . . . . . . . . . . . . . .
Wiring Harness Service 6E±220. . . . . . . . . . . . . . . .
Connectors and Terminals 6E±220. . . . . . . . . . . . . .
Wire Harness Repair: Twisted Shielded
Cable 6E±220. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal Procedure 6E±220. . . . . . . . . . . . . . . . . . . .
Installation Procedure 6E±221. . . . . . . . . . . . . . . . . .
Twisted Leads 6E±221. . . . . . . . . . . . . . . . . . . . . . . . . .
Removal Procedure 6E±221. . . . . . . . . . . . . . . . . . . .
Installation Procedure 6E±222. . . . . . . . . . . . . . . . . .
Weather-Pack Connector 6E±223. . . . . . . . . . . . . . . . .
Tools Required 6E±223. . . . . . . . . . . . . . . . . . . . . . . .
Removal Procedure 6E±223. . . . . . . . . . . . . . . . . . . . Installation Procedure 6E±223. . . . . . . . . . . . . . . . . .
Com-Pack III 6E±224. . . . . . . . . . . . . . . . . . . . . . . . . . .
General Information 6E±224. . . . . . . . . . . . . . . . . . . .
Metri-Pack 6E±224. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tools Required 6E±224. . . . . . . . . . . . . . . . . . . . . . . .
Removal Procedure 6E±224. . . . . . . . . . . . . . . . . . . .
Installation Procedure 6E±224. . . . . . . . . . . . . . . . . .
General Description
(ECM and Sensors) 6E±225. . . . . . . . . . . . . . . . . . . . .
57X Reference ECM Input 6E±225. . . . . . . . . . . . . .
A/C Request Signal 6E±225. . . . . . . . . . . . . . . . . . . .
Crankshaft Position (CKP) Sensor 6E±225. . . . . . .
Camshaft Position (CMP) Sensor and
Signal 6E±225. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Coolant Temperature (ECT) Sensor 6E±225
Electrically Erasable Programmable Read
Only Memory (EEPROM) 6E±225. . . . . . . . . . . . . .
Intake Air Temperature (IAT) Sensor 6E±225. . . . .
Manifold Absolute Pressure (MAP) Sensor 6E±226
Engine Control Module (ECM) 6E±226. . . . . . . . . . .
ECM Function 6E±226. . . . . . . . . . . . . . . . . . . . . . . . .
ECM Components 6E±226. . . . . . . . . . . . . . . . . . . . .
ECM Voltage Description 6E±226. . . . . . . . . . . . . . .
ECM Input/Outputs 6E±226. . . . . . . . . . . . . . . . . . . .
ECM Service Precautions 6E±227. . . . . . . . . . . . . .
Intake Throttle Position (ITP) Sensor 6E±227. . . . .
Transmission Range Switch 6E±227. . . . . . . . . . . . .
Accelerator Position Sensor (AP) 6E±227. . . . . . . .
Aftermarket Electrical and Vacuum
Equipment 6E±227. . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrostatic Discharge Damage 6E±227. . . . . . . . .
General Description (Air Induction) 6E±228. . . . . . . .
Air Induction System 6E±228. . . . . . . . . . . . . . . . . . .
General Description (Fuel Metering) 6E±228. . . . . . .
Deceleration Mode 6E±228. . . . . . . . . . . . . . . . . . . .
Fuel Injector 6E±228. . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Metering System Components 6E±228. . . . . .
A/C Clutch Diagnosis 6E±228. . . . . . . . . . . . . . . . . . . .
A/C Request Signal 6E±228. . . . . . . . . . . . . . . . . . . .
General Description Exhaust Gas
Recirculation (EGR) System 6E±228. . . . . . . . . . . . .
EGR Purpose 6E±228. . . . . . . . . . . . . . . . . . . . . . . . .
Fuse and Relay Panel
(Underhood Electrical Center) RHD 6E±229. . . . . . .
Fuse and Relay Panel
(Underhood Electrical Center) LHD 6E±230. . . . . . .