sensor ISUZU TROOPER 1998 Service Repair Manual

6E±213 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
3. Connect the electrical connector to the AP sensor.
035RW060
4. Connect the negative battery cable.
Fuel Filter Cap
General Description
The fuel filler cap includes a vacuum valve and a pressure
valve.
If high vacuum or high pressure occurs in the fuel tank,
each valve works to adjust the pressure in order to
prevent damage to the tank at the EGR valve.
TS23767
Inspection Procedure
NOTE: Replace the fuel filler cap with the same type of
filler cap that was originally installed on the vehicle.

Check the seal ring in the filler cap for any abnormality
and for seal condition.

Replace the filler cap if any abnormality is found.
Fuel Filter
Removal and Installation Procedure
Refer to the Engine fuel in the 4JX1 Engine section.
Fuel Gauge Unit
Removal Procedure
1. Disconnect the negative battery cable.
2. Loosen the fuel filler cap.
3. Drain the fuel from the tank.
Tighten

Tighten the drain plug to 20 N´m (14 lb ft.).
TS22907
4. Disconnect the wiring connector from the fuel gauge
unit.
TS23771
5. Remove the fuel gauge unit retaining screws.

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.

6E±215 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
4. Remove the rear side engine hanger.
035RW070
5. Remove the fuel return adapter.
035RW069
6. Remove the fuel pressure sensor from the fuel return
adapter.
035RW068
Installation Procedure
1. Install the fuel pressure sensor in the fuel return
adapter.
035RW068

6E±216
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
2. Install the fuel return adapter.
035RW069
3. Install the rear side engine hanger. Tighten the rear
side engine hanger fixing bolts to specified torque.
Torque: 19 N´m (14 lb ft)
035RW070
4. Install the cylinder head. Refer to engine mechanical
section.
5. Install the intercooler assembly.
6. Connect the negative battery cable.
Rail Pressure (RP) Sensor
Removal Procedure
1. Disconnect the negative battery cable.
2. Remove the air cleaner cover and air duct.
3. Remove the intercooler assembly.
4. Remove the injector oil pipe.
5. Remove the intake throttle valve.
6. Remove the cylinder head cover noise inselation.
7. Remove the cylinder head cover.
8. Remove the RP sensor.
Installation Procedure

Refer to the RP Sensor Programming.
1. Install the RP sensor.
2. Install the cylinder head cover.
3. Install the cylinder head cover noise inselation.
4. Install the intake throttle valve.
5. Install the injector oil pipe.
6. Install the intercooler assembly and tighten
intercooler assembly fixing bolts to specified torque.
Torque: 20 N´m (14 lb ft)
7. Install the air cleaner cover and air duct.
8. Connect the negative battery cable.
Fuel Tank
Removal Procedure
Refer toEngine Fuel in 4JX1 Engine section.
060RW068

6E±217 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Throttle Body (TB)
Removal Procedure
1. Disconnect the negative battery cable.
2. Remove the cover of the intercooler.
035RW051
3. Remove the bolts and the left side bracket to the
intercooler.
4. Remove the air duct with bracket from the intercooler.
035RW086
5. Remove the throttle body assembly from the intake
manifold.
6. Disconnect the ITP sensor electrical connector.
Installation 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.
1. Install the throttle body assembly to the intake
manifold and the air duct with bracket between
throttle body and intercooler.
Torque: 20 N´m (14 Ib ft)
035RW086
2. Connect the ITP sensor electrical connector and
throttle motor control connector.
3. Install the bracket to the intercooler.
4. Install the cover of intercooler.
5. Connect the negative battery cable.
Air Conditioning (A/C) Relay
Removal Procedure
1. Remove the fuse and relay box cover from under the
hood.
2. Consult the diagram on the cover to determine which
is the correct relay.
3. Pull the relay straight up and out of the fuse and relay
box.
Installation Procedure
1. Insert the relay into the correct place in the fuse and
relay box with the catch slot facing forward.
2. Press down until the catch engages.

An audible ªclickº will be heard.
3. Install the fuse and relay box cover.
Exhaust Gas Recirculation
(EGR) Vacuum Switch Valve
(VSV)
Removal Procedure
1. Disconnect the negative battery cable.

6E±218
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
2. Disconnect the EGR VSV connector and vacuum
hose from the EGR VSV.
035RW063
3. Remove the MAP sensor assembly and EGR VSV.
035RW067
4. Remove the EGR VSV from the MAP sensor bracket.
035RW062
Installation Procedure
1. Install the EGR VSV and tighten nut to specified
torque.
Torque: 8 N´m (69 lb in)
035RW062

6E±219 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
2. Install the MAP sensor assembly and EGR VSV and
tighten MAP sensor bracket fixing bolts specified
torque.
Torque: 9 N´m (78 lb in)
035RW067
3. Connect the EGR VSV connector and vacuum hose
in the EGR VSV.
035RW063
4. Connect the negative battery cable.
Electronic Vacuum Regurating
Valve (EVRV)
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the EVRV hose and the EVRV connector.
035RW065
3. Remove the EVRV.
035RW064

6E±220
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Installation Procedure
1. Install the EVRV.
035RW064
2. Connect the EVRV hose and the EVRV connector.
035RW065
3. Connect the negative battery cable.
Wiring and Connectors
Wiring Harness Service
The ECM harness electrically connects the ECM to the
various solenoids, switches and sensors in the vehicle
engine compartment and passenger compartment.
Replace wire harnesses with the proper part number
replacement.
Because of the low amperage and voltage levels utilized
in powertrain control systems, it is essential that all wiring
in environmentally exposed areas be repaired with crimp
and seal splice sleeves.The following wire harness repair information is intended
as a general guideline only. Refer to
Chassis Electrical for
all wire harness repair procedures.
Connectors and Terminals
Use care when probing a connector and when replacing
terminals. It is possible to short between opposite
terminals. Damage to components could result. Always
use jumper wires between connectors for circuit
checking. NEVER probe through Weather-Pack seals.
Use an appropriate connector test adapter kit which
contains an assortment of flexible connectors used to
probe terminals during diagnosis. Use an appropriate
fuse remover and test tool for removing a fuse and to
adapt the fuse holder to a meter for diagnosis.
Open circuits are often difficult to locate by sight because
oxidation or terminal misalignment are hidden by the
connectors. Merely wiggling a connector on a sensor, or
in the wiring harness, may temporarily correct the open
circuit. Intermittent problems may also be caused by
oxidized or loose connections.
Be certain of the type of connector/terminal before
making any connector or terminal repair. Weather-Pack
and Com-Pack III terminals look similar, but are serviced
differently.
Wire Harness Repair: Twisted
Shielded Cable
Removal Procedure
1. Remove the outer jacket.
2. Unwrap the aluminum/mylar tape. Do not remove the
mylar.
047

6E±224
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
5. Push the terminal and the connector to engage the
locking tangs.
070
6. Close the secondary locking hinge.
Com-Pack III
General Information
The Com-Pack III terminal looks similar to some
Weather-Pack terminals. This terminal is not sealed and
is used where resistance to the environment is not
required. Use the standard method when repairing a
terminal. Do not use the Weather-Pack terminal tool
5-8840-0388-0 or equivalent. These will damage the
terminals.
Metri-Pack
Tools Required
5-8840-0632-0 Terminal Remover
Removal Procedure
Some connectors use terminals called Metri-Pack Series
150. These may be used at the engine coolant
temperature (ECT) sensor.
1. Slide the seal (1) back on the wire.2. Insert the 5-8840-0632-0 tool or equivalent (3) in
order to release the terminal locking tang (2).
060
3. Push the wire and the terminal out through the
connector. If you reuse the terminal, reshape the
locking tang.
Installation Procedure
Metri-Pack terminals are also referred to as ªpull-to-seatº
terminals.
1. In order to install a terminal on a wire, the wire must be
inserted through the seal (2) and through the
connector (3).
2. The terminal (1) is then crimped onto the wire.
061
3. Then the terminal is pulled back into the connector to
seat it in place.

6E±225 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
General Description
(ECM and Sensors)
57X Reference ECM Input
The engine control module (ECM) uses this signal from
the crankshaft position (CKP) sensor to calculate engine
RPM and crankshaft position at all engine speeds. The
ECM also uses the pulses on this circuit to initiate injector
pulses. If the ECM receives no pulses on this circuit, DTC
P0337 will set. The engine will not start and run without
using the 57X reference signal.
A/C Request Signal
This signal tells the ECM when the A/C mode is selected
at the A/C control head.
Refer to
A/C Clutch Circuit Diagnosis for A/C wiring
diagrams and diagnosis for the A/C electrical system.
Crankshaft Position (CKP) Sensor
The crankshaft position (CKP) sensor provides a signal
used by the engine control module (ECM) to calculate the
ignition sequence. The CKP sensor initiates the 57X
reference pulses which the ECM uses to calculate RPM
and crankshaft position.
Refer to
Electronic Ignition System for additional
information.
Camshaft Position (CMP) Sensor and
Signal
The camshaft position (CMP) sensor sends a CMP signal
to the ECM. The ECM uses this signal as a ªcylinder
distinctionº to trigger the injectors in the power order. If the
ECM detects an incorrect CMP signal while the engine is
running, DTC P0341 will set, and the ECM triggers the
injectors in the power order.
Refer to
DTC P0341.
Engine Coolant Temperature (ECT) Sensor
The engine coolant temperature (ECT) sensor is a
thermistor (a resistor which changes value based on
temperature) mounted in the engine coolant stream. Low
coolant temperature produces a high resistance of
100,000 ohms at ±40
C (±40
F). High temperature
causes a low resistance of 70 ohms at 130
C (266
F).
The ECM supplies a 5-volt signal to the ECT sensor
through resistors in the ECM and measures the voltage.
The signal voltage will be high when the engine is cold and
low when the engine is hot. By measuring the voltage, the
ECM calculates the engine coolant temperature. Engine
coolant temperature affects most of the systems that the
ECM controls.
The Tech 2 displays engine coolant temperature in
degrees. After engine start-up, the temperature should
rise steadily to about 85
C (185
F). It then stabilizes
when the thermostat opens. If the engine has not been
run for several hours (overnight), the engine coolanttemperature and intake air temperature displays should
be close to each other. A hard fault in the engine coolant
sensor circuit will set DTC P0117 or DTC P0118.
0016
Electrically Erasable Programmable Read
Only Memory (EEPROM)
The electrically erasable programmable read only
memory (EEPROM) is a permanent memory chip that is
physically soldered within the ECM. The EEPROM
contains the program and the calibration information that
the ECM needs to control powertrain operation.
Unlike the PROM used in past applications, the EEPROM
is not replaceable. If the ECM is replaced, the new ECM
will need to be programmed. Equipment containing the
correct program and calibration for the vehicle is required
to program the ECM.
Intake Air Temperature (IAT) Sensor
The intake air temperature (IAT) sensor is a thermistor
which changes its resistance based on the temperature of
air entering the engine. Low temperature produces a high
resistance of 100,000 ohms at ±40
C (±40
F). High
temperature causes low resistance of 70 ohms at 130
C
(266
F) . The ECM supplies a 5-volt signal to the sensor
through a resistor in the ECM and monitors the signal
voltage. The voltage will be high when the incoming air is
cold. The voltage will be low when the incoming air is hot.
By measuring the voltage, the ECM calculates the
incoming air temperature.
The Tech 2 displays the temperature of the air entering
the engine. The temperature should read close to the
ambient air temperature when the engine is cold and rise
as underhood temperature increases. If the engine has
not been run for several hours (overnight), the IAT sensor
temperature and engine coolant temperature should read
close to each other. A fault in the IAT sensor circuit will set
DTC P0112 or DTC P0113.