1998 ISUZU TROOPER Remove gas tank

AIR CONDITIONING 1B Ð 5
With some compressors the differential between
the intake pressure and discharge pressure
generated while the compressor is operating is
used for lubrication instead of an oil pump.
The specified amount of the DKV-14D, DKS-15CH
and HD6 compressors oil is 150cc (4.2 Imp fl oz).
Also, compressor oil to be used varies according to
the compressor model. Be sure to avoid mixing
two or more different types of oil.
If the wrong oil is used, lubrication will be poor and
the compressor will seize or malfunction.
The magnetic clutch connector is a waterproof type.
MAGNETIC CLUTCH
The compressor is driven by the drive belt from the
crank pulley of the engine. If the compressor is
activated each time the engine is started, this
causes too much load to the engine. The magnetic
clutch transmits the power from the engine to the
compressor and activates it when the air
conditioning is ÒONÓ. Also, it cuts off the power
from the engine to the compressor when the air
conditioning is ÒOFFÓ. (Magnetic clutch repair
procedure can be found in Section 1D.)
CONDENSER
The condenser assembly in front of the radiator,
which carry the refrigerant and cooling fins to
provide rapid transfer of heat.
Also, it functions to cool and liquefy the high-
pressure and high-temperature vapor sent from the
compressor by the radiator fan or outside air.
A condenser may malfunction in two ways: it may
leak, or it may be restricted. A condenser restriction
will result in excessive compressor discharge
pressure. If a partial restriction is present, the
refrigerant expands after passing through the
restriction.
Thus, ice or frost may from immediately after the
restriction. If air flow through the condenser or
radiator is blocked, high discharge pressures will
result. During normal condenser operation, the
refrigerant outlet line will be slightly cooler than the
inlet line.
The vehicle is equipped with the condenser of the
parallel flow type condenser. A larger thermal
transmission area on the inner surface of the tube
allows the radiant heat to increase and the
ventilation resistance to decrease.
The refrigerant line connection has a bolt at the
block joint, for easy servicing.
RECEIVER/DRIER
The receiver/drier performs four functions;
·As the quantity of refrigerant circulated varies
depending on the refrigeration cycle conditions,
sufficient refrigerant is stored for the refrigera-
tion cycle to operate smoothly in accordance
with fluctuations in the quantity circulated.
·The liquefied refrigerant from the condenser is
mixed with refrigerant gas containing air
bubbles. If refrigerant containing air bubbles is
sent to the expansion valve, the cooling
capacity will decrease considerably. Therefore,
the liquid and air bubbles are separated and
only the liquid is sent to the expansion valve.
·The receiver/drier utilizes a filter and dryer to
remove the dirt and water mixed in the cycling
refrigerant.
·The sight glass, installed atop the receiver/
drier, show the state of the refrigerant.
A receiver/drier may fail due to a restriction inside
the body of the unit. A restriction at the inlet to the
receiver/drier will cause high pressures.
Outlet restrictions will be indicated by low pressure
and little or no cooling. An excessively cold
receiver/ drier outlet may indicate a restriction.
The receiver/drier of this vehicle is made of
aluminum with a smaller tank. It has 300 cc
(8.5 Imp fl oz) refrigerant capacity.
The refrigerant line connection has a bolt at the
block joint, for easy servicing.
DKV-14D TYPE
DKS-15CH TYPE
HD6 TYPE
Magnetic clutch
CompressorSuction side
Discharge side
Compressor Magnetic clutch
852RW031 871RY00012
871RY00011

6C±3
ENGINE FUEL

Adhere to all Notices and Cautions.
All gasoline engines are designed to use only unleaded
gasoline. Unleaded gasoline must be used for proper
emission control system operation.
Its use will also minimize spark plug fouling and extend
engine oil life. Using leaded gasoline can damage the
emission control system and could result in loss of
emission warranty coverage.
All cars are equipped with an Evaporative Emission
Control System. The purpose of the system is to minimize
the escape of fuel vapors to the atmosphere.
Fuel Metering
The Engine Control Module (ECM) is in complete control
of this fuel delivery system during normal driving
conditions.
The intake manifold function, like that of a diesel, is used
only to let air into the engine. The fuel is injected by
separate injectors that are mounted over the intake
manifold.
The Manifold Absolute Pressure (MAP) sensor measures
the changes in the intake manifold pressure which result
from engine load and speed changes, which the MAP
sensor converts to a voltage output.
This sensor generates the voltage to change
corresponding to the flow of the air drawn into the engine.
The changing voltage is transformed into an electric
signal and provided to the ECM.
With receipt of the signals sent from the MAP sensor,
Intake Air Temperature sensor and others, the ECM
determines an appropriate fuel injection pulse width
feeding such information to the fuel injector valves to
effect an appropriate air/fuel ratio.
The Multiport Fuel Injection system utilizes an injection
system where the injectors turn on at every crankshaft
revolution. The ECM controls the injector on time so that
the correct amount of fuel is metered depending on
driving conditions.
Two interchangeable ªOº rings are used on the injector
that must be replaced when the injectors are removed.
The fuel rail is attached to the top of the intake manifold
and supplies fuel to all the injectors.
Fuel is recirculated through the rail continually while the
engine is running. This removes air and vapors from the
fuel as well as keeping the fuel cool during hot weather
operation.
The fuel pressure control valve that is mounted on the fuel
rail maintains a pressure differential across the injectors
under all operating conditions. It is accomplished by
controlling the amount of fuel that is recirculated back to
the fuel tank based on engine demand.
See Section ªDriveability and Emissionº for more
information and diagnosis.

6E±91 ENGINE DRIVEABILITY AND EMISSIONS
Fuel System Diagnosis

 
StepNo Ye s Value(s) Action
10Locate and repair the loss of vacuum to the fuel
pressure regulator.
Is the action complete?
ÐVerify repairÐ
11Replace the fuel pressure regulator.
Is the action complete?
ÐVerify repairÐ
121. Run the fuel pump with Tech 2.
2. After pressure has built up, turn off the pump and
clamp the supply hose shut with suitable locking
pliers.
Does the fuel pressure indicated by the fuel pressure
gauge remain constant?
ÐGo to Step 13Go to Step 15
13Visually inspect the fuel supply line and repair any
leaks.
Was a problem found?
ÐVerify repairGo to Step 14
14Remove the fuel tank and inspect for leaky hose or
in-tank fuel line.
Was a problem found?
ÐVerify repairGo to Step 8
151. If the pliers are still clamped to the fuel supply hose,
remove the locking pliers.
2. With suitable locking pliers, clamp the fuel return
line to prevent fuel from returning to the fuel tank.
3. Run the fuel pump with Tech 2.
4. After pressure has built up, remove power to the
pump.
Does the fuel pressure indicated by the fuel pressure
gauge remain constant?
ÐGo to Step 11Go to Step 16
16Locate and replace any leaking fuel injector(s).
Is the action complete?
ÐVerify repairÐ
17Is the fuel pressure indicated by the fuel pressure
gauge above the specified limit?376 kPa
(55 psi)
Go to Step 18Go to Step 21
181. Relieve the fuel pressure. Refer to the Fuel
Pressure Relief.
2. Disconnect the fuel return line from the fuel rail.
3. Attach a length of flexible hose to the fuel rail return
outlet passage.
4. Place the open end of the flexible hose into an
approved gasoline container.
5. Run the fuel pump with Tech 2.
6. Observe the fuel pressure indicated by the fuel
pressure gauge with the fuel pump running.
Is the fuel pressure within the specified limits?
290-376 kPa
(42-55 psi)
Go to Step 19Go to Step 20
19Locate and correct the restriction in the fuel return line.
Is the action complete?
ÐVerify repairÐ
20Visually and physically inspect the fuel rail outlet
passages for a restriction.
Was a restriction found?
ÐVerify repairGo to Step 11
21Is the fuel pressure indicated by the fuel pressure
gauge above the specified value?
0 kPa (0 psi)Go to Step 22Go to Step 23

6E±314
ENGINE DRIVEABILITY AND EMISSIONS
3. Connect the wiring connector to the fuel gauge unit.
TS23771
4. Fill the fuel tank with fuel.

Tighten the fuel filler cap.

Check for leaks at the fuel gauge unit gasket.
5. Connect the negative battery cable.
Fuel Injectors
Removal Procedure
NOTE: If the fuel injectors are leaking, the engine oil may
be contaminated with fuel. Check the oil for signs of
contamination and change the oil and the filter if
necessary.
NOTE: Use care in removing the fuel injectors in order to
prevent damage to the fuel injector electrical connector
pins or the fuel injector nozzles. The fuel injector is an
electrical component and should not be immersed in any
type of cleaner as this may damage the fuel injector.
IMPORTANT:Fuel injectors are serviced as a complete
assembly only.
1. Disconnect the negative battery cable.
2. Remove the upper intake manifold. Refer to
Common Chamber in Engine Mechanical..
3. Remove the fuel rail. Refer to
Fuel Rail.
014RW164
4. Remove the injector retainer clip.
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5. Remove the fuel injector assembly.
6. Remove the O-ring from the fuel injector.
7. Remove the O-ring backup from the fuel injector .
Inspection Procedure
1. Inspect the O-rings for cracks or leaks.
2. Replace worn or damaged O-rings.
3. Lubricate the new O-rings with engine oil before
installation.

6E±318
ENGINE DRIVEABILITY AND EMISSIONS
2. Remove the fuel pump relay from the underhood
relay box. Refer to
Fuel Pump Relay.
TS23976R
3. Start the engine and allow it to stall.
4. Crank the engine for 30 seconds.
5. Disconnect the negative battery cable.
Fuel Pump Assembly
Removal Procedure
1. Disconnect the negative battery cable.
2. Drain all the fuel from the tank.
3. Install and tighten the drain plug.
Tighten

Tighten the drain plug to 20 N´m (14 lb ft.).
4. Remove the fuel tank. Refer to
Fuel Tank.
5. Remove the retaining screws from the fuel tank.
6. Remove the fuel pump assembly from the fuel tank.

Cover the fuel pump opening in order to prevent
dust, dirt, or debris from entering the fuel tank.
TS23795
Inspection Procedure
1. Inspect the fuel pump gasket for tears, cracks,
stretching, or rotting. If any of these conditions are
found, replace the fuel pump gasket.
2. Inspect the in-tank fuel filter for tears or evidence of
dirt, debris, or water in the fuel. If any of these
conditions are found, replace the in-tank fuel filter.
Installation Procedure
1. Install the fuel pump assembly.
2. Install the fuel pump assembly retaining screws.
3. Install the fuel tank assembly. Refer to
Fuel Tank.
4. Fill the tank with fuel.
5. Tighten the fuel filler cap.
6. Connect the negative battery cable.
TS23795

6E±323 ENGINE DRIVEABILITY AND EMISSIONS
11. Connect the fuel filler fuse at the tank.
12. Connect the air breather hose at the tank.
TS23796
13. Fill the fuel tank with fuel.
14. Tighten the fuel filler cap.
15. Connect the negative battery cable.
Throttle Body (TB)
Removal Procedure
1. Disconnect the negative battery cable.
2. Drain the cooling system. Refer to
Cooling System.
3. Remove the accelerator cable assembly. Refer to
Accelerator Cable in Engine Speed Control System..
4. Disconnect the electrical connectors:

Throttle position (TP) sensor.

Idle air control (IAC) solenoid.

Intake air temperature (IAT) sensor. Refer to
Intake Air Temperature Sensor.
035RW023
5. Disconnect the vacuum hose below the air horn.
6. Remove the intake air duct clamp.
7. Disconnect the intake air duct.
8. Disconnect the coolant lines from the throttle body.
9. Remove the bolts from the common chamber.
10. Remove the throttle body from the common chamber.
11. Remove the gasket from the upper intake manifold.
035RW024
12. Remove the IAC. Refer to Idle Air Control (IAC)
Solenoid
.
13. Remove the TP sensor. Refer to
Throttle Position
(TP) Sensor
.
Inspection Procedure
NOTE: Do not use solvent of any type when you clean the
gasket surfaces on the intake manifold and the throttle
body assembly. The gasket surfaces and the throttle
body assembly may be damaged as a result.

If the throttle body gasket needs to be replaced,
remove any gasket material that may be stuck to the
mating surfaces of the manifold.

Do not leave any scratches in the aluminum casting.
Installation Procedure
1. Install the TP sensor. Refer to Throttle Position (TP)
Sensor
.
2. Install the IAC. Refer to
Idle Air Control (IAC)
Solenoid
.
3. Install the gasket on the common chamber.
4. Install the throttle body on the common chamber.

6E±328
ENGINE DRIVEABILITY AND EMISSIONS
3. Connect the vacuum hoses to the EVAP canister
purge solenoid.
014RW137
4. Connect the electrical connector to the EVAP canister
purge solenoid.
014RW138
Fuel Tank Vent Valve
Removal and Installation Procedure
Refer to Fuel Pump
Linear Exhaust Gas
Recirculation (EGR) Valve
Removal Procedure
1. Disconnect the negative battery cable.2. Disconnect the electrical connector at the EGR valve.
014RW139
3. Remove the bolt and the nut from the upper intake
manifold.
014RW098
4. Remove the EGR valve from the upper intake
manifold.
5. Remove the gasket from the upper intake manifold.
Installation Procedure
1. Install the gasket on the upper intake manifold.
2. Install the EGR valve on the upper intake manifold.
3. Secure the EGR valve and the gasket with the bolt
and the nut.

6E±214
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
6. Remove the fuel gauge unit.

Cover or plug the fuel tank to prevent dust, dirt, or
debris from entering the tank.
TS22911
Installation Procedure
1. Install the fuel gauge unit.
2. Install the fuel gauge unit retaining screws.
TS22911
3. Connect the wiring connector to the fuel gauge unit.
TS23771
4. Fill the fuel tank with fuel.

Tighten the fuel filler cap.

Check for leaks at the fuel gauge unit gasket.
5. Connect the negative battery cable.
Fuel Injectors
Removal and Installation Procedure
Refer to Engine Fuel in 4JX1 Engine Section.
Fuel Temperature Sensor
Removal Procedure
CAUTION: To reduce the risk of fire and personal
injury, it is necessary to relieve the fuel system
pressure before servicing the fuel system
components.
CAUTION: After relieving the system pressure, a
small amount of fuel may be released when servicing
fuel lines or connections. Reduce the chance of
personal injury by covering the fuel line fittings with
a shop towel before disconnecting the fittings. The
towels will absorb any fuel that may leak out. When
the disconnect is completed, place the towel in an
approved container.
1. Disconnect the negative battery cable.
2. Remove the intercooler assembly.
3. Remove the cylinder head. Refer to engine
mechanical section.