1998 ISUZU TROOPER Intake sensor

6E±227 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS

QOS

Diagnostics
± Malfunction Indicator Lamp (Service Engine
Soon lamp)
± Data Link Connector (DLC)
± Data Output
ECM Service Precautions
The ECM is designed to withstand normal current draws
associated with vehicle operation. Avoid overloading any
circuit. When testing for opens and shorts, do not ground
or apply voltage to any of the ECM's circuits unless
instructed to do so. These circuits should only be tested
using digital voltmeter. The ECM should remain
connected to the ECM or to a recommended breakout
box.
Intake Throttle Position (ITP) Sensor
ITP sensor is a potentiometer type and installed to the
intake throttle valve body. A voltage of 5V is applied
constantly from ECM to ITP sensor thereby to determine
by change in voltage the opening of the intake throttle
valve during warming up.
Transmission Range Switch
IMPORTANT:The vehicle should not be driven with the
transmission range switch disconnected; idle quality will
be affected.
The four inputs from the transmission range switch
indicate to the ECM which position is selected by the
transmission selector lever.
For more information on the transmission on the
transmission range switch, refer to
Automatic
Transmission
.
Accelerator Position Sensor (AP)
AP sensor is a potentiometer type and installed to
accelerator pedal bracket. A voltage of 5V constantly
applied from ECM to the sensor thereby to determine the
accelerator pedaling angle by change in voltage. Further,
this sensor is provided with an accelerator switch, which
is set off only when the accelerator pedal is stepped on.
Aftermarket Electrical and Vacuum
Equipment
Aftermarket (add-on) electrical and vacuum equipment is
defined as any equipment which connects to the vehicle's
electrical or vacuum systems that is installed on a vehicle
after it leaves the factory. No allowances have been
made in the vehicle design for this type of equipment.
NOTE: No add-on vacuum equipment should be added
to this vehicle.
NOTE: A d d - o n e l e c t r i c a l equipment must only be
connected to the vehicle's electrical system at the battery
(power and ground).
Add-on electrical equipment, even when installed to
these guidelines, may still cause the powertrain system to
malfunction. This may also include equipment not
connected to the vehicle electrical system such asportable telephones and radios. Therefore, the first step
in diagnosing any powertrain problem is to eliminate all
aftermarket electrical equipment from the vehicle. After
this is done, if the problem still exists, it may be diagnosed
in the normal manner.
Electrostatic Discharge Damage
Electronic components used in the ECM are often
designed to carry very low voltage. Electronic
components are susceptible to damage caused by
electrostatic discharge. Less than 100 volts of static
electricity can cause damage to some electronic
components. By comparison, it takes as much as 4000
volts for a person to feel even the zap of a static
discharge.
TS23793
There are several ways for a person to become statically
charged. The most common methods of charging are by
friction and induction.

An example of charging by friction is a person sliding
across a vehicle seat.

Charge by induction occurs when a person with well
insulated shoes stands near a highly charged object
and momentary touches ground. Charges of the
same polarity are drained off leaving the person
highly charged with the opposite polarity. Static
charges can cause damage, therefore it is important
to use care when handling and testing electronic
components.
NOTE: To p r e ve n t p ossible electrostatic discharge
damage, follow these guidelines:

Do not touch the ECM connector pins or soldered
components on the ECM circuit board.

Do not open the replacement part package until the
part is ready to be installed.

Before removing the part from the package, ground
the package to a known good ground on the vehicle.

If the part has been handled while sliding across the
seat, while sitting down from a standing position, or
while walking a distance, touch a known good ground
before installing the part.

6E±228
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
General Description (Air Induction)
Air Induction System
The air induction system filters contaminants from the
outside air, and directs the progress of the air as it is
drawn into the engine. A remote-mounted air cleaner
prevents dirt and debris in the air from entering the
engine. The air duct assembly routes filtered air to the
throttle body. Air enters the engine by to following steps:
1. Through the throttle body.
2. Into the intake manifold.
3. Through the cylinder head intake ports.
4. Into the cylinders.
General Description (Fuel Metering)
Deceleration Mode
The ECM reduces the amount of fuel injected when it
detects a decrease in the Accelerator position.
Fuel Injector
Fuel injector comprises the solenoid, hydraulic line, and
fuel line. Fuel injection is controlled by the continuity time
signal and continuity start timing signal from ECM to the
solenoid
ECM determines the running conditions of engine by
input signals such as engine speed. Accelerator throttle
valve opening, and engine coolant temperature, thereby
to send the solenoid the best suited signal to the engine
status. When current is carried to the solenoid, the
armature opens the poppet valve to alow high pressure oil
to run into the injector. Under the pressure of the oil, the
piston and plunger are depressed to compress the fuel in
the combustion chamber of the plunger. Specifically, the
pressure of the fuel compressed is increased by a piston
top/ plunger bottom area ratio over the pressure of high
pressure oil, thereby lifting the fuel nozzle end needle for
injecting fuel.
Fuel Metering System Components
The fuel metering system is made up of the following
parts:

The fuel injectors.

The intake throttle body.

The Accelerator position (AP) sensor

The ECM.

The crankshaft position (CKP) sensor.

The camshaft position (CMP) sensor.
Basic System Operation
Fuel is supplied through fuel filter to the fuel pump.
The fuel pump is installed to the oil pump, and fuel is
forced, through the fuel pump outlet, pipe and cylinder
head inside, into the fuel injector.
An orifice is provided at the rear fuel outlet of cylinder
head to control the pressure of oil.The injector is controlled by ECM which gives
opening/closing commands to the solenoid installed on
the top of the injector. Opening/closing operation of the
pressurized engine oil circuit of the injector controls fuel
injection quantity, fuel injection timing, etc.
A/C Clutch Diagnosis
A/C Request Signal
This signal tells the ECM when the A/C mode is selected
at the A/C control head. The ECM uses this to adjust the
idle speed.
Refer to
A/C Clutch Circuit Diagnosis for A/C wiring
diagrams and diagnosis for A/C electrical system.
General Description Exhaust Gas
Recirculation (EGR) System
EGR Purpose
The exhaust gas recirculation (EGR) system is use to
reduce emission levels of oxides of nitrogen (NOx). NOx
emission levels are caused by a high combustion
temperature. The EGR system lowers the NOx emission
levels by decreasing the combustion temperature.
The ECM uses information from the following sensors to
control EGR valve boost pressure.

ECT

ITP

Engine Speed

AP sensor

6J – 10 INDUCTION
REMOVAL
1. Remove intercooler assembly.
Refer to “Intercooler” in this manual.
2. Remove harness connector from motor and ITP
sensor.
3. Loosen the two fixing nuts and remove the throttle
valve assembly.
Legend
(1) Motor
(2) Intake Throttle Valve
(3) ITP sensor
INSPECTION AND REPAIR
1. Check for catching somwhere on the throttle valve.
2. If some problem is discovered during inspection on
the throttle valve, the throttle valve must replace.
INSTALLATION
1. Put gasket on the intake manifold and install throttle
valve.
2. Tighten nuts to the specified torque.
Torque: 20 N·m (2.0 kg·m / 14.5 lb ft)
3. Reconnect harness connector to motor and
ITPsensor.
4. Install intercooler assembly.
1 2 3
025RW032
INTAKE THROTTLE VALVE

INDUCTION 6J – 11
INTAKE MANIFOLD
REMOVAL
1. Drain engine coolant and remove water hose from
thermostat housing
2. Remove intercooler assembly.
3. Remove bracket fixing bolt of oil level gauge guide
tube.
4. Remove PCV hose.
5. Remove hoses from EGR valve, EGR vacuum
sensor and outlet of heater unit.
6. Disconnect harness connector from MAP sensor,
EGR vacuum sensor, ETC sensor, Water
temperature unit, IAT sensor and EVRV.
7. Remove high pressure oil pipe.
8. Remove two way check valve.
9. Remove fuel pipe.
10. Remove fixing bolts and nuts of intake manifold,
remove intake manifold assembly.
Legend
(1) Intake manifold
(2) Fixing portion of throttle valve
(3) EGR passage
(4) EGR valve
For Europe
2
1
3
3 1 42
Legend
(1) Intake Manifold
(2) Throttle Valve Assembly
(3) EGR Valve
(4) Gasket
025R200005
3124
025RW031

6J – 12 INDUCTION
INSPECTION AND RAPAIR
1. Visually check for cracks/clogs inside intake
manifold.
2. If foreign material is observed, it should be taken
out, and if there are some cracks on the intake
manifold, it must be replaced.
INSTALLATION
1. Install the intake manifold assembly, tighten bolts
and to the specified torque.
Torque: 20 N·m (2.0 kg·m / 14.5 lb ft) for bolt
Torque: 20 N·m (2.0 kg·m / 14.5 lb ft) for nut
2. Install fuel pipe.
Torque: 4 N·m (0.4 kg·m / 2.9 lb ft) for M16 nut
(Apply engine oil)
Torque: 13 N·m (1.3 kg·m / 9.4 lb ft) for M10 cap nut
Torque: 14 N·m (1.4 kg·m / 10 lb ft) for M10
(Apply engine oil)
3. Install two way check valve.
Torque: 20 N·m (2.0 kg·m / 14.5 lb ft)
4. Fill with about 300 cc 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.
5. Install high pressure oil pipe, then tighten sleeve nut
to the specified torque.
Torque: 29 N·m (3.0 kg·m / 21.7 lb ft)
6. Reconnect harness connector to MAP sensor, EGR
vacuum sensor, ETC sensor, Water thermo unit,
IAT sensor and EVRV sensor.
7. Install hoses to EGR valve, EGR vacuum sensor
and Water outlet of heater.
8. Connect PCV hose.
9. Install oil level gauge guide and fix it.
10. Install intercooler assembly.
Refer to “Intercooler” in this manual.
11. Install water hose to thermostat housing and fill with
engine coolant.
Model of Turbocharger IHI RHF5
Turbine Maximum Speed 180,000 rpm
Maximum Inlet Gas Temperature 800 °C (1472 °F)
Vibration Peak (G) criteria Maximum 4 (G) at Turbine Rotor Speed 140,000 rpm
Tolerance Limit of Compressor Blade Height Less then 0.5 mm (0.0197 in)
MAIN DATA AND SPECIFICATIONS

WIRING SYSTEM 8DÐ85
Circuit Diagram (RHD 6V
*1)Ð5
F
C
VSV : VACUUM SWITCHING VALVE
PCM : POWERTRAIN CONTROL MODULE
P C M
0.85
B/Y
C-3H-6H-4168 H-412
E5
0.5
R/L0.8
R/L
VSV ;
DUTY
SOLENOID
0.8
B/YC-1E-8H-67E-8
1 2
A15 0.85
B/Y
0.85
B/Y
0.5
Y/B0.5
W/L
VSV ;
INTAKE
AIRINTAKE AIR
TEMPERATURE
SENSORTHROTTLE
POSITION
SENSOR
0.5
B/YC-2E-44
E-33
H-49E-44
2 1
C11
0.85
Y 0.8
Y
C-3H-415E-33
1
E6
0.85
Y/R0.8
Y/R
C-1H-414E-33
3
B7
0.85
R 0.8
R0.8
G0.8
G0.8
Y/G0.8
G
0.8
L0.8
R 0.8
B/Y
C-1H-413E-33
4 5
A1
0.85
Y/G
C-1H-59E-43
1
E-43
2
E-5
2
B8
0.75
GC-2H-66E-5
1
D8
0.75
L0.5
B0.5
B/R
1.25
B/P
1.0
B/R
COMMON CHAMBER
C-2
13
H-5E-29
H-65E-5
3
E8
E-33
2
EGR VALVE
3
1
C-88
D08RW591

8DÐ100 WIRING SYSTEM
Circuit Diagram (LHD 6V
*1)Ð5
F
C
VSV : VACUUM SWITCHING VALVE
PCM : POWERTRAIN CONTROL MODULE
P C M
0.85
B/Y
C-3H-6H-4168 H-412
E5
0.5
R/L0.8
R/L
VSV ;
DUTY
SOLENOID
0.8
B/YC-1E-8H-67E-8
1 2
A15 0.85
B/Y
0.85
B/Y
0.5
Y/B0.5
W/L
VSV ;
INTAKE
AIRINTAKE AIR
TEMPERATURE
SENSORTHROTTLE
POSITION
SENSOR
0.5
B/YC-2E-44
E-33
H-49E-44
2 1
C11
0.85
Y 0.8
Y
C-3H-415E-33
1
E6
0.85
Y/R0.8
Y/R
C-1H-414E-33
3
B7
0.85
R 0.8
R0.8
G0.8
G0.8
Y/G0.8
G
0.8
L0.8
R 0.8
B/Y
C-1H-413E-33
4 5
A1
0.85
Y/G
C-1H-59E-43
1
E-43
2
E-5
2
B8
0.75
GC-2H-66E-5
1
D8
0.75
L0.5
B0.5
B/R
1.25
B/P
1.0
B/R
COMMON CHAMBER
C-2
13
H-5E-29
H-65E-5
3
E8
E-33
2
EGR VALVE
3
1
C-88
D08RW591

8DÐ118 WIRING SYSTEM
QOS and EGR System (4JG2)
General Description
The circuit consists of the starter switch, QOS/EGR
control unit, glow relay, charge relay, fuel cut
solenoid, dropping resistor, thermo sensor, glow
indicator light (meter), glow plug, vehicle speed
sensor, tacho sensor, throttle position sensor, EVRV
and VSV; EGR.
The engine coolant temperature at the time of the
engine start-up is sensed by the thermo sensor to
change the glow time so that the optimum starting
conditions can always be obtained.
The idling speed just after the engine start-up can
also be placed in the most suitable conditions in
accordance with the coolant temperature by the
operation of the delay timer.The indicator timer is activated upon the starter
switch turned to the ON position, and the indicator
light comes on for as much time as suitable for the
engine coolant temperature at the time of the
engine start-up.
EGR system controls the information of NOx by
returning a small amount of exhaust gas from the
intake manifold to the combustion chamber
through the EGR valve.