1998 ISUZU TROOPER Intake sensor

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. . . . . . .

6E±19 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Component Locator
Engine Component Locator Table
F06RW051
NumberNameLocation
1AP (Accelerator Pedal Position) SensorAP Bracket
2CKP (Crankshaft Position) SensorInside the right front flywheel Housing
3Oil RailMounted on the camshaft carrier
4Oil (Rail) Pressure SensorMounted on the Oil Rail
5OT (Oil Temperature) SensorMounted on the Oil Rail
6Fuel InjectorIn the Cylinder Head Cover
7Fuel Return OrificeInside the Cylinder Head
8FT (Fuel Temperature) SensorFuel Return Adaptor
9IntercoolerOn the Cylinder Head Cover
10Intake Throttle MotorBehind the Intake Manifold
11Intake ThrottleBehind the Intake Manifold
122 Way Check ValveBelow the Intake Manifold
13VSV (Vacuum Switching Valve)At the left Cylinder Body
14EGR Pressure SensorBelow the Intake Manifold
15Fuel FilterAt the left Engine Room
16CMP (Camshaft Position) SensorOn the forward of Timing Gear Case
17IAT (Intake Air Temperature) SensorBelow the Intake Manifold
18ECT (Engine Coolant Temperature)Thermostat Housing
19High Pressure Oil PumpOn the back Timing Gear Case

6E±20
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
NumberNameLocation
20Rail Pressure Control ValveIn the High Pressure Oil Pump
21Fuel PumpIn the High Pressure Oil Pump
22EVRVOn the Intake Manifold
23MAP (Manifold Absolute Pressure) SensorOn the Intake Manifold
24EGR ValveOn the Intake Manifold
25Air CleanerAt the left Engine Room
26ECMBehind the Air Cleaner

6E±23 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Abbreviations Charts
List of abbreviations which may be used in this section.
Abbreviations
TermAbbreviationsTerm
A/CAir ConditionerBLKBlack
A/TAutomatic TransmissionBLUBlue
ACCAccessoryBRNBrown
APAccel PositionGRNGreen
ASMAssemblyGRYGray
CKPCrank PositionLT BLULight Blue
CMPCam PositionLT GRNLight Green
DLCData Link ConnectorORNOrange
DTCDiagnosis Trouble CodePNKPink
DVMDigital Volt MeterREDRed
ECMEngine Control ModuleVIOViolet
ECTEngine Coolant TemperatureWHTWhite
EGRExhaust Gas RecircurationYELYellow
EVRVElectric Vacuum Regulating Valve
EXHExhaust
FTFuel Temperature
IATIntake Air Temperature
IGIgnition
ITPIntake Throttle Position
M/TManual Transmission
MAPManifold Absolute Pressure
MILMulfunction Indicator Lamp
OBDOn-Board Diagnostic
OTOil Temperature
QOSQuick on Start System
QWSQuick Warming-Up System
RPRail Pressure
RPCVRail Pressure Control Valve
SRSSupplemental Restraint System
STStart
SWSwitch
TEMPTemperature
TODTorque on Demand
VSSVehicle Speed Sensor
VSVVacuum Switching Valve
HEUIHydraulically Actuated Electronically Controlled Unit
InjectorInjector

6E±25 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
General Service Information
Serviceability Issues
Non-OEM Parts
All of the OBD diagnostics have been calibrated to run
with OEM parts. Accordingly, if commercially sold sensor
or switch is installed, it makes a wrong diagnosis and turn
on the MIL (ªCheck Engineº lamp).
Aftermarket electronics, such as cellular phones,
stereos, and anti-theft devices, may radiate EMI into the
control system if they are improperly installed. This may
cause a false sensor reading and turn on the MIL (ªCheck
Engineº lamp).
Poor Vehicle Maintenance
The sensitivity of OBD diagnostics will cause the MIL
(ªCheck Engineº lamp) to turn on if the vehicle is not
maintained properly. Restricted oil filters, fuel filters, and
crankcase deposits due to lack of oil changes or improper
oil viscosity can trigger actual vehicle faults that were not
previously monitored prior to OBD. Poor vehicle
maintenance can not be classified as a ªnon-vehicle
faultº, but with the sensitivity of OBD diagnostics, vehicle
maintenance schedules must be more closely followed.
Related System Faults
Many of the OBD system diagnostics will not run if the
ECM detects a fault on a related system or component.
Visual/Physical Engine Compartment
Inspection
Perform a careful visual and physical engine
compartment inspection when performing any diagnostic
procedure or diagnosing the cause of an emission test
failure. This can often lead to repairing a problem without
further steps. Use the following guidelines when
performing a visual/physical inspection:

Inspect all vacuum hoses for punches, cuts,
disconnects, and correct routing.

Inspect hoses that are difficult to see behind other
components.

Inspect all wires in the engine compartment for proper
connections, burned or chafed spots, pinched wires,
contact with sharp edges or contact with hot exhaust
manifolds or pipes.
Basic Knowledge of Tools Required
NOTE: Lack of basic knowledge of this powertrain when
performing diagnostic procedures could result in an
incorrect diagnosis or damage to powertrain
components. Do not attempt to diagnose a powertrain
problem without this basic knowledge.
A basic understanding of hand tools is necessary to effec-
tively use this section of the Service Manual.
Serial Data Communications
Class II Serial Data Communications
This vehicle utilizes the ªClass IIº communication system.
Each bit of information can have one of two lengths: longor short. This allows vehicle wiring to be reduced by
transmitting and receiving multiple signals over a single
wire. The messages carried on Class II data streams are
also prioritized. If two messages attempt to establish
communications on the data line at the same time, only
the message with higher priority will continue. The device
with the lower priority message must wait.
On this vehicle the Tech 2 displays the actual values for
vehicle parameters. It will not be necessary to perform
any conversions from coded values to actual values.
On-Board Diagnostic (OBD)
On-Board Diagnostic Tests
A diagnostic test is a series of steps, the result of which is
a pass or fail reported to the diagnostic executive. When
a diagnostic test reports a pass result, the diagnostic
executive records the following data:

The diagnostic test has been completed since the last
ignition cycle.

The diagnostic test has passed during the current
ignition cycle.

The fault identified by the diagnostic test is not
currently active.
When a diagnostic test reports a fail result, the diagnostic
executive records the following data:

The diagnostic test has been completed since the last
ignition cycle.

The fault identified by the diagnostic test is currently
active.

The fault has been active during this ignition cycle.

The operating conditions at the time of the failure.
Comprehensive Component Monitor
Diagnostic Operation
Comprehensive component monitoring diagnostics are
required to operate engine properly.
Input Components:
Input components are monitored for circuit continuity and
out-of-range values. This includes rationality checking.
Rationality checking refers to indicating a fault when the
signal from a sensor does not seem reasonable. Accel
Position (AP) sensor that indicates high throttle position
at low engine loads or MAP voltage. Input components
may include, but are not limited to the following sensors:

Intake Air Temperature (IAT) Sensor

Crankshaft Position (CKP) Sensor

Intake throttle Position (ITP) Sensor

Engine Coolant Temperature (ECT) Sensor

Camshaft Position (CMP) Sensor

Manifold absolute Pressure (MAP) Sensor

Accel Position Sensor

Fuel Temp Sensor

Rail Pressure Sensor

Oil Temp Sensor

EGR Pressure Sensor

Vehicle Speed Sensor

6E±26
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Output Components:
Output components are diagnosed for proper response to
control module commands. Components where
functional monitoring is not feasible will be monitored for
circuit continuity and out-of-range values if applicable.
Output components to be monitored include, but are not
limited to, the following circuit:

EGR VSV

EGR EVRV

Electronic Transmission controls

Injector

Intake throttle

Glow plug

MIL control
Refer to ECM and Sensors in General Descriptions.
Passive and Active Diagnostic Tests
A passive test is a diagnostic test which simply monitors a
vehicle system or component. Conversely, an active test,
actually takes some sort of action when performing
diagnostic functions, often in response to a failed passive
test.
Intrusive Diagnostic Tests
This is any on-board test run by the Diagnostic
Management System which may have an effect on
vehicle performance or emission levels.
Warm-Up Cycle
A warm-up cycle means that engine at temperature must
reach a minimum of 70
C (160
F)
and rise at least 22
C
(40
F) over the course of a trip.
Freeze Frame
Freeze Frame is an element of the Diagnostic
Management System which stores various vehicle
information at the moment an emissions-related fault is
stored in memory and when the MIL is commanded on.
These data can help to identify the cause of a fault. Refer
to
Storing And Erasing Freeze Fame Data for more
detailed information.
Failure Records
Failure Records data is an enhancement of the OBD
Freeze Frame feature. Failure Records store the same
vehicle information as does Freeze Frame, but it will store
that information for any fault which is stored in on-board
memory, while Freeze Frame stores information only for
emission-related faults that command the MIL on.
Common OBD Terms
Diagnostic
When used as a noun, the word diagnostic refers to any
on-board test run by the vehicle's Diagnostic
Management System. A diagnostic is simply a test run on
a system or component to determine if the system or
component is operating according to specification. There
are many diagnostics, shown in the following list:

EGR

engine speed

vehicle speed

ECT
MAP

VSV

IAT

ITP

AP

FT (Fuel Temp)

RP (Rail Pressure)

OT (Oil Temp)

EGR EVRV

Idle SW

Brake SW
The Diagnostic Executive
The Diagnostic Executive is a unique segment of
software which is designed to coordinate and prioritize
the diagnostic procedures as well as define the protocol
for recording and displaying their results. The main
responsibilities of the Diagnostic Executive are listed as
follows:

Commanding the MIL (ªCheck Engineº lamp) on and
off

DTC logging and clearing

Freeze Frame data for the first emission related DTC
recorded

Current status information on each diagnostic
Diagnostic Information
The diagnostic charts and functional checks are designed
to locate a faulty circuit or component through a process
of logical decisions. The charts are prepared with the
requirement that the vehicle functioned correctly at the
time of assembly and that there are not multiple faults
present.
There is a continuous self-diagnosis on certain control
functions. This diagnostic capability is complemented by
the diagnostic procedures contained in this manual. The
language of communicating the source of the malfunction
is a system of diagnostic trouble codes. When a
malfunction is detected by the control module, a
diagnostic trouble code is set and the Malfunction
Indicator Lamp (MIL) (ªCheck Engineº lamp) is
illuminated.
Malfunction Indicator Lamp (MIL)
The Malfunction Indicator Lamp (MIL) looks the same as
the MIL you are already familiar with ªCheck Engineº
lamp.
Basically, the MIL is turned on when the ECM detects a
DTC that will impact the vehicle emissions.

When the MIL remains ªONº while the engine is
running, or when a malfunction is suspected due to a
driveability or emissions problem, a Powertrain
On-Board Diagnostic (OBD) System Check must be
performed. The procedures for these checks are
given in On-Board Diagnostic (OBD) System Check.
These checks will expose faults which may not be
detected if other diagnostics are performed first.
DTC Types
Characteristic of Code

6E±34
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Fuel Injection System
060RW178
Legend
(1) ECM
(2) Meter Panel
(3) Battery
(4) Oil Temp Sensor
(5) Rail Pressure Sensor
(6) Glow Relay
(7) Oil Rail
(8) Tech±2
(9) A/C Comp Relay
(10) RPCV
(11) Intake Air Temp Sensor
(12) Engine Coolant Temp Sensor
(13) MAP Sensor
(14) EGR Valve
(15) EGR Pressure Sensor(16) High Pressure Oil Pump
(17) Fuel Pump
(18) VSV
(19) EXH Throttle VSV1
(20) EXH Throttle VSV2
(21) EVRV
(22) Engine Harness Connector
(23) QWS Relay
(24) APS
(25) T.O.D
(26) ECT
(27) OBD
(28) TDC
(29) Injector
(30) Edge Filter

6E±39 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Engine Control Module ECM
Diagnosis
To read and clear diagnostic trouble codes, use a Tech 2.
IMPORTANT:Use of a Tech 2 is recommended to clear
diagnostic trouble codes from the ECM memory.
Diagnostic trouble codes can also be cleared by turning
the ignition ªOFFº and disconnecting the battery power
from the ECM for 30 seconds. Turning off the ignition and
disconnecting the battery power from the ECM will cause
all diagnostic information in the ECM memory to be
cleared. Therefore, all the diagnostic tests will have to be
re-run.
Since the ECM can have a failure which may affect only
one circuit, following the diagnostic procedures in this
section will determine which circuit has a problem and
where it is.
If a diagnostic chart indicates that the ECM connections
or the ECM is the cause of a problem, and the ECM is
replaced, but this does not correct the problem, one of the
following may be the reason:

There is a problem with the ECM terminal
connections. The terminals may have to be removed
from the connector in order to check them properly.

The problem is intermittent. This means that the
problem is not present at the time the system is being
checked. In this case, refer to the
Symptoms portion
of the manual and make a careful physical inspection
of all components and wiring associated with the
affected system.

There is a shorted solenoid, relay coil, or harness.
Solenoids and relays are turned ªONº and ªOFFº by
the ECM using internal electronic switches called
drivers. A shorted solenoid, relay coil, or harness will
not damage the ECM but will cause the solenoid or
relay to be inoperative.
Multiple ECM Information Sensor
DTCS Set
Circuit Description
The Engine Control Module ECM monitors various
sensors to determine the engine operating conditions.
The ECM controls fuel delivery, spark advance,
transmission operation, and emission control device
operation based on the sensor inputs.
The ECM provides a sensor ground to all of the sensors.
The ECM applies 5 volts through a pull-up resistor, and
determines the status of the following sensors by
monitoring the voltage present between the 5-volt supply
and the resistor:

The fuel temperature (FT) sensor

The engine coolant temperature (ECT) sensor

The Intake air temperature (IAT) sensor
The ECM provides the following sensors with a 5-volt
reference and a sensor ground signal:

The Intake throttle position sensor

The manifold absolute pressure sensor

The rail pressure sensor

The accelerator position sensor

The oil temperature sensor
The camshaft position sensor

The crankshaft position sensor

The EGR pressure sensor
The ECM monitors the signals from these sensors in
order to determine their operating status.
Diagnostic Aids
IMPORTANT:Be sure to inspect ECM and engine
grounds for being secure and clean.
A short to voltage in one of the sensor input circuits may
cause one or more of the following DTCs to be set:

P0337

P0342

P1193

P1404

P1405

P1488
IMPORTANT:If a sensor input circuit has been shorted
to voltage, ensure that the sensor is not damaged. A
damaged sensor will continue to indicate a high or low
voltage after the affected circuit has been repaired. If the
sensor has been damaged, replace it.
An open in the sensor ground circuit between the ECM
and the splice will cause one or more of the following
DTCs to be set:

P0337

P0342

P0117
A short to ground in the 5-volt reference A or B circuit will
cause one or more of the following DTCs to be set:

P0112

P0117

P0182

P0197
An open in the 5-volt reference circuit A, between the
ECM and the splice will cause one or more of the following
DTCs to be set:

P0107

P0405

P1194

P0122
An open in the 5-volt reference circuit B, between the
ECM and the splice will cause one or more of the following
DTCs to be set:

P1485
Check for the following conditions:

Poor connection at ECM. Inspect the harness
connectors for backed-out terminals, improper
mating, broken locks, improperly formed or damage
terminals, and a poor terminal-to-wire connection.

Damaged harness. Inspect the wiring harness for
damage. If the harness is not damaged, observe an
affected sensor's displayed value on the Tech 2 with
the ignition ªONº and the engine ªOFFº while you
move the connectors and the wiring harnesses
related to the following sensors:

ECT Sensor