service OPEL FRONTERA 1998 Workshop Manual
[x] Cancel search | Manufacturer: OPEL, Model Year: 1998, Model line: FRONTERA, Model: OPEL FRONTERA 1998Pages: 6000, PDF Size: 97 MB
Page 4987 of 6000

6E–330
ENGINE DRIVEABILITY AND EMISSIONS
Wiring and Connectors
Wiring Harness Service
The  control  module  harness  electrically  connects  the
control  module  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 f o r
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.
PCM Connectors and Terminals
Removal Procedure
1. Remove the connector terminal retainer.
2. Push  the  wire  connected  to  the  affected  terminal
through  the  connector  face  so  that  the  terminal  is
exposed.
3. Service the terminal as necessary.
Installation Procedure
1. Bend the tab on the connector to allow the terminal to
be pulled into position within the connector.
2. Pull  carefully  on  the  wire  to  install  the  connector
terminal retainer.
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
3. Untwist the conductors.
4. Strip the insulation as necessary.
048 
Page 4995 of 6000

6E–338
ENGINE DRIVEABILITY AND EMISSIONS
RPM.  A failure in the MAF sensor or circuit will set DTC
P0101, DTC P0102, or DTC P0103.
0007
Manifold Absolute Pressure (MAP) Sensor
The manifold absolute pressure (MAP) sensor responds
to  changes  in  intake  manifold  pressure  (vacuum).    The
MAP sensor signal voltage to the PCM varies from below
2  volts  at  idle  (high  vacuum)  to  above  4  volts  with  the
ignition ON,  engine  not  running or  at  wide-open  throttle
(low vacuum).
The MAP sensor is used to determine the following:
Manifold pressure changes while the linear EGR flow
test diagnostic is being run.  Refer to 
DTC P0401.
Engine vacuum level for other diagnostics.
Barometric pressure (BARO).
If  the  PCM  detects  a  voltage  that  is  lower  than  the
possible range of the MAP sensor, DTC P0107 will be set.
A  signal  voltage  higher  than  the  possible  range  of  the
sensor  will  set  DTC  P0108.   An  intermittent  low  or  high
voltage will set DTC P1107 or DTC P1106, respectively.
The  PCM  can  detect  a  shifted  MAP  sensor.    The  PCM
compares  the  MAP  sensor  signal  to  a  calculated  MAP
based on throttle position and various engine load factors.
If the PCM detects a MAP signal that varies excessively
above or below the calculated value, DTC P0106 will set.
055RW004
Powertrain Control Module (PCM)
The  powertrain  control  module  (PCM)  is  located  in  the
passenger compartment below the center console.  The
PCM controls the following:
Fuel metering system.
Transmission shifting (automatic transmission only).
Ignition timing.
On-board diagnostics for powertrain functions.
The  PCM  constantly  observes  the  information  from
various  sensors.    The  PCM  controls  the  systems  that
affect  vehicle  performance.    The  PCM  performs  the
diagnostic  function  of  the  system.    It  can  recognize
operational  problems,  alert  the  driver  through  the  MIL
(Service Engine Soon lamp), and store diagnostic trouble
codes (DTCs).  DTCs identify the problem areas to aid the
technician in making repairs.
This engine uses 2 different control modules:
IPCM-6KT  for  automatic  transmission-equipped
vehicles.
ISFI-6 for manual transmission-equipped vehicles.
PCM Function
The PCM supplies either 5 or 12 volts to power various
sensors  or  switches.    The  power  is  supplied  through
resistances in the PCM which are so high in value that a
test  light  will  not  light  when  connected  to  the  circuit.    In
some cases, even an ordinary shop voltmeter will not give
an  accurate  reading  because  its  resistance  is  too  low.
Therefore, a digital voltmeter with at least 10 megohms
input impedance is  required to  ensure  accurate voltage
readings. Tool J 39200 meets this requirement.  The PCM
controls output circuits such as the injectors, IAC, cooling
fan  relays,  etc.,  by  controlling  the  ground  or  the  power
feed circuit through transistors of following device.
Output Driver Module (ODM) 
Page 4996 of 6000

6E–339 ENGINE DRIVEABILITY AND EMISSIONS
0005
PCM Components
The PCM is designed to maintain exhaust emission levels
to  government  mandated  standards  while  providing
excellent  driveability  and  fuel  efficiency.    The  PCM
monitors  numerous  engine  and  vehicle  functions  via
electronic  sensors  such  as  the  throttle  position  (TP)
sensor,  heated  oxygen  sensor  (HO2S),  and  vehicle
speed  sensor  (VSS).    The  PCM  also  controls  certain
engine operations through the following:
Fuel injector control
Ignition control module
Knock sensor
Automatic transmission shift functions
Cruise control
A/C clutch control
PCM Voltage Description
The PCM supplies a buffered voltage to various switches
and  sensors.    It  can  do  this  because  resistance  in  the
PCM is so high in value that a test light may not illuminate
when  connected  to  the  circuit.    An  ordinary  shop
voltmeter may not give an accurate reading because the
voltmeter input impedance is too low.  Use a 10-megohm
input  impedance  digital  voltmeter  (such  as  J  39200)  to
assure accurate voltage readings.
The  input/output  devices  in  the  PCM  include
analog-to-digital  converters,  signal  buffers,  counters,
and special drivers.  The PCM controls most components
with electronic switches which complete a ground circuit
when turned “ON.”  These switches are arranged in
groups of 4 and 7, called either a surface-mounted quad
driver module (QDM), which can independently control up
to 4 output terminals, or QDMs which can independently
control up to 7 outputs.  Not all outputs are always used.
PCM Input/Outputs
Inputs – Operating Conditions Read
Air Conditioning “ON” or “OFF” 
Engine Coolant Temperature
Crankshaft Position
Exhaust Oxygen Content
Electronic Ignition
Manifold Absolute Pressure
Battery Voltage
Throttle Position
Vehicle Speed
Fuel Pump Voltage
Power Steering Pressure
Intake Air Temperature
Mass Air Flow
Engine Knock
Camshaft Position
Outputs – Systems Controlled
Exhaust Gas Recirculation (EGR)
Ignition Control
Fuel Control
Idle Air Control
Electric Fuel Pump
Air Conditioning
Diagnostics
– Malfunction  Indicator  Lamp  (Service  Engine  Soon
lamp)
– Data Link Connector (DLC)
– Data Output
Transmission Control Module
Alternator Gain Control
PCM Service Precautions
The PCM 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  PCM’s  circuits  unless
instructed to do so.  These circuits should only be tested
Tech-2.  The PCM should remain connected to the PCM
or to a recommended breakout box.
Reprogramming The PCM
The  Trooper  allow  reprogramming  of  the  PCM  without
removing it from the vehicle .  This provides a flexible and
cost-effective  method  of  making  changes  in  software
calibrations.
The  service  programming  system  (SPS)  will  not  allow
incorrect  software  programming  or  incorrect  calibration
changes.
Refer  to  the  UBS  98model  year  Immobilizer  Workshop
Manual.
Throttle Position (TP) Sensor
The  throttle  position  (TP)  sensor  is  a  potentiometer
connected to the throttle shaft on the throttle body.  The
PCM  monitors  the  voltage  on  the  signal  line  and
calculates throttle position.  As the throttle valve angle is
changed (accelerator pedal moved), the TP sensor signal
also changes.  At a closed throttle position, the output of 
Page 5000 of 6000

6E–343 ENGINE DRIVEABILITY AND EMISSIONS
constant measuring and adjusting of the air/fuel ratio, the
fuel injection system is called a “closed loop” system.
The PCM monitors signals from several sensors in order
to  determine  the  fuel  needs  of  the  engine.  Fuel  is
delivered under one of several conditions called “modes.”
All modes are controlled by the PCM.
Fuel Pressure Regulator
The  fuel  pressure  regulator  is  a  diaphragm-operated
relief  valve  mounted  on  the  fuel  rail  with  fuel  pump
pressure on one side and manifold pressure on the other
side.    The  fuel  pressure  regulator  maintains  the  fuel
pressure  available  to  the  injector  at  three  times
barometric pressure adjusted for engine load.  It may be
serviced separate.
If the pressure is too low, poor performance and a DTC
P0131, DTC P0151,DTC P0171 or DTC P1171 will be the
result.  If the pressure is too high, excessive odor and/or a
DTC P0132, DTC P0152,DTC P0172 or DTC P0175 will
be  the  result.    Refer  to 
Fuel  System  Diagnosis for
information on diagnosing fuel pressure conditions.
0011
Fuel Pump Electrical Circuit
When the key is first turned “ON,” the PCM energizes the
fuel  pump  relay  for  two  seconds  to  build  up  the  fuel
pressure  quickly.    If  the engine  is  not  started within two
seconds, the PCM shuts the fuel pump off and waits until
the engine is cranked.  When the engine is cranked and
the 58 X crankshaft position signal has been detected by
the PCM, the PCM supplies 12 volts to the fuel pump relay
to energize the electric in-tank fuel pump.
An inoperative fuel pump will cause a “no-start” condition.
A fuel pump which does not provide enough pressure will
result in poor performance.
Fuel Rail
The  fuel  rail  is  mounted  to  the  top  of  the  engine  and
distributes  fuel  to  the  individual  injectors.    Fuel  is
delivered to the fuel inlet tube of the fuel rail by the fuel
lines.    The  fuel  goes  through  the  fuel  rail  to  the  fuel
pressure regulator.  The fuel pressure regulator maintainsa constant fuel pressure at the injectors.  Remaining fuel
is then returned to the fuel tank.
055RW009
Idle Air Control (IAC) Valve
The purpose of the idle air control (IAC) valve is to control
engine idle speed, while preventing stalls due to changes
in  engine  load.    The  IAC  valve,  mounted  in  the  throttle
body,  controls  bypass  air  around  the  throttle  plate.    By
moving the conical valve (pintle) in (to decrease air flow)
or out  (to increase air flow), a controlled amount of air can
move around the throttle plate.  If the RPM is too low, the
PCM  will  retract  the  IAC  pintle,  resulting  in  more  air
moving past the throttle plate to increase the RPM.  If the
RPM  is  too  high,  the  PCM  will  extend  the  IAC  pintle,
allowing  less  air  to  move  past  the  throttle  plate,
decreasing the RPM.
The IAC pintle valve moves in small steps called counts.
During  idle,  the  proper  position  of  the  IAC  pintle  is
calculated by the PCM based on battery voltage, coolant
temperature, engine load, and engine RPM.  If the RPM
drops  below  a  specified  value,    and  the  throttle  plate  is
closed, the PCM senses a near-stall condition. The PCM
will  then  calculate  a  new  IAC  pintle  valve  position  to
prevent stalls.
If the IAC valve is disconnected and reconnected with the
engine running, the idle RPM will be wrong.  In this case,
the IAC must be reset.  The IAC resets when the key is
cycled  “ON”  then  “OFF.”    When  servicing  the  IAC,  it
should  only  be  disconnected  or  connected  with  the
ignition “OFF.”
The position of the IAC pintle valve affects engine start-up
and the idle characteristics of the vehicle.  If the IAC pintle
is fully open, too much air will be allowed into the manifold.
This results in high idle speed, along with possible hard
starting  and  a  lean  air/fuel  ratio.    DTC  P0507  or  DTC
P1509 may set.  If the IAC pintle is stuck closed, too little
air will be allowed in the manifold.  This results in a low idle
speed, along with possible hard starting and a rich air/fuel
ratio.    DTC  P0506  or  DTC  P1508  may  set.    If  the  IAC
pintle is stuck part-way open, the idle may be high or low
and will not respond to changes in the engine load. 
Page 5004 of 6000

6E–347 ENGINE DRIVEABILITY AND EMISSIONS
the  secondary  ignition  circuit  to  flow  through  the  spark
plug to the ground.
TS24047
Ignition Control PCM Output
The PCM provides a zero volt (actually about 100 mV to
200 mV) or a 5-volt output signal to the ignition control (IC)
module.    Each  spark  plug  has  its  own  primary  and
secondary coil module (”coil-at-plug”) located at the spark
plug itself.  When the ignition coil receives the 5-volt signal
from the PCM, it provides a ground path for the B+ supply
to the primary side of the coil-at -plug module.  This
energizes the primary coil and creates a magnetic field in
the  coil-at-plug  module.    When  the  PCM  shuts  off  the
5-volt  signal  to  the  ignition  control  module,  the  ground
path for the primary coil is broken.  The magnetic field
collapses and induces a high voltage secondary impulse
which fires the spark plug and ignites the air/fuel mixture.
The  circuit  between  the  PCM  and  the  ignition  coil  is
monitored for open circuits, shorts to voltage, and shorts
to ground.  If the PCM detects one of these events, it will
set one of the following DTCs:
P0351:  Ignition coil Fault on Cylinder #1
P0352:  Ignition coil Fault on Cylinder #2
P0353:  Ignition coil Fault on Cylinder #3
P0354:  Ignition coil Fault on Cylinder #4
P0355:  Ignition coil Fault on Cylinder #5
P0356:  Ignition coil Fault on Cylinder #6
Knock Sensor (KS) PCM Input
The knock sensor (KS) system is comprised of a knock
sensor and the PCM.  The PCM monitors the KS signals
to  determine  when  engine  detonation  occurs.    When  a
knock  sensor  detects  detonation,  the  PCM  retards  the
spark timing to  reduce detonation.   Timing  may  also  be
retarded  because  of  excessive  mechanical  engine  or
transmission noise.
Powertrain Control Module (PCM)
The PCM is responsible for maintaining proper spark and
fuel injection timing for all driving conditions.  To provideoptimum  driveability  and  emissions,  the  PCM  monitors
the input signals from the following components in order
to calculate spark timing:
Engine coolant temperature (ECT) sensor.
Intake air temperature (IAT) sensor.
Mass air flow (MAF) sensor.
PRNDL input from transmission range switch.
Throttle position (TP) sensor.
Vehicle speed sensor (VSS) .
Crankshaft position (CKP) sensor.
Spark Plug
Although worn or dirty spark plugs may give satisfactory
operation  at  idling  speed,  they  frequency  fail  at  higher
engine speeds.  Faulty spark plugs may cause poor fuel
economy,  power  loss,  loss  of  speed,  hard  starting  and
generally  poor  engine  performance.    Follow  the
scheduled  maintenance  service  recommendations  to
ensure  satisfactory  spark  plug  performance.    Refer  to
Maintenance and Lubrication.
Normal  spark  plug  operation  will  result  in  brown  to
grayish-tan deposits appearing on the insulator portion of
the spark plug.  A small amount of red-brown, yellow, and
white  powdery  material  may  also  be  present  on  the
insulator tip around the center electrode.  These deposits
are  normal  combustion  by-products  of  fuels  and
lubricating oils with additives.  Some electrode wear will
also occur.  Engines which are not running properly are
often referred to as  “misfiring.”    This  means the  ignition
spark is not igniting the air/fuel mixture at the proper time.
While other ignition and fuel system causes must also be
considered,  possible  causes  include  ignition  system
conditions which allow the spark voltage to reach ground
in some other manner than by jumping across the air gap
at  the  tip  of  the  spark  plug,  leaving  the  air/fuel  mixture
unburned.  Misfiring  may  also  occur  when  the  tip  of  the
spark plug becomes overheated and ignites the mixture
before  the  spark  jumps.  This  is  referred  to  as
“pre-ignition.”
Spark  plugs  may  also  misfire  due  to  fouling,  excessive
gap, or a cracked or broken insulator.  If misfiring occurs
before  the  recommended  replacement  interval,  locate
and correct the cause.
Carbon fouling of the spark plug is indicated by dry, black
carbon (soot) deposits on the portion of the spark plug in
the  cylinder.      Excessive  idling  and  slow  speeds  under
light engine loads can keep the spark plug temperatures
so  low  that  these  deposits  are  not  burned  off.  Very  rich
fuel mixtures or poor ignition system output may also be
the cause.  Refer to DTC P0172.
Oil  fouling  of  the  spark  plug  is  indicated  by  wet  oily
deposits on the portion of the spark plug in the cylinder,
usually with little electrode wear.  This may be caused by
oil during break-in of new or newly overhauled engines.
Deposit fouling of the spark plug occurs when the normal
red-brown,  yellow  or  white  deposits  of  combustion  by
products become  sufficient to cause misfiring.  In some
c a s e s ,  t h e s e  d e p o s i t s  m a y  m e l t  a n d  f o r m  a  s h i n y  g l a z e  o n
the insulator around the center electrode.  If the fouling is
found in only one or two cylinders, valve stem clearances
or intake valve seals may be allowing excess lubricating 
Page 5006 of 6000

6E–349 ENGINE DRIVEABILITY AND EMISSIONS
Damage during re-gapping can happen if the gapping
tool  is  pushed  against  the  center  electrode  or  the
insulator  around  it,  causing  the  insulator  to  crack.
When re-gapping a spark plug, make the adjustment
by bending only the ground side terminal, keeping the
tool clear of other parts.
”Heat  shock”  breakage  in  the  lower  insulator  tip
generally  occurs  during  several  engine  operating
conditions (high speeds or heavy loading) and may be
caused by over-advanced timing or low grade fuels.
Heat  shock  refers  to  a  rapid  increase  in  the  tip
temperature  that  causes  the  insulator  material  to
crack.
Spark plugs with less than the recommended amount of
service can sometimes be cleaned and re-gapped , then
returned to service.  However, if there is any doubt about
the serviceability of a spark plug, replace it.  Spark plugs
with  cracked  or  broken  insulators  should  always  be
replaced.
A/C Clutch Diagnosis
A/C Clutch Circuit Operation
A 12-volt signal is supplied to the A/C request input of the
PCM  when  the  A/C  is  selected  through  the  A/C  control
switch.
The A/C compressor clutch relay is controlled through the
PCM.  This allows the PCM to modify the idle air control
position prior to the A/C clutch engagement for better idle
quality.  If the engine operating conditions are within their
specified  calibrated  acceptable  ranges,  the  PCM  will
enable  the  A/C  compressor  relay.    This  is  done  by
providing a ground path for the A/C relay coil within the
PCM.    When  the  A/C  compressor  relay  is  enabled,
battery voltage is supplied to the compressor clutch coil.
The  PCM  will  enable  the A/C  compressor  clutch
whenever  the  engine  is  running  and  the  A/C  has  been
requested.  The PCM will not enable the A/C compressor
clutch if any of the following conditions are met:
The throttle is greater than  90%.
The engine speed is greater than 6315 RPM.
The ECT is greater than 119C (246F).
The IAT is less than 5C (41F).
The throttle is more than 80% open.
A/C Clutch Circuit Purpose
The  A/C  compressor  operation  is  controlled  by  the
powertrain  control  module  (PCM)  for  the  following
reasons:
It  improvises  idle  quality  during  compressor  clutch
engagement.
It improvises wide open throttle (WOT) performance.
It provides A/C compressor protection from operation
with incorrect refrigerant pressures.
The  A/C  electrical  system  consists  of  the  following
components:
The A/C control head.
The A/C refrigerant pressure switches.
The A/C compressor clutch.
The A/C compressor clutch relay.
The PCM.
A/C Request Signal
This signal tells the PCM when the A/C mode is selected
at the A/C control head.  The PCM uses this to adjust the
idle  speed  before  turning  on  the  A/C  clutch.    The  A/C
compressor  will  be  inoperative  if  this  signal  is  not
available to the PCM.
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.
057RW002
Linear EGR Valve
The main element of the system is the linear EGR valve.
The EGR valve feeds small amounts of exhaust gas back
into the combustion chamber.  The fuel/air mixture will be
diluted and combustion temperatures reduced.
Linear EGR Control
The PCM monitors the EGR actual positron and adjusts
the pintle position accordingly.  The uses information from
the following sensors to control the pintle position:
Engine coolant temperature (ECT) sensor.
Throttle position (TP) sensor.
Mass air flow (MAF) sensor.
Linear EGR Valve Operation and Results
of Incorrect Operation
The  linear  EGR  valve  is  designed  to  accurately  supply
EGR  to  the  engine  independent  of  intake  manifold
vacuum.  The valve controls EGR flow from the exhaust 
Page 5012 of 6000

6F–1 ENGINE EXHAUST
ENGINE
ENGINE EXHAUST
CONTENTS
Service Precaution 6F–1. . . . . . . . . . . . . . . . . . . . . . 
General Description 6F–2. . . . . . . . . . . . . . . . . . . . . 
Front Exhaust Pipe 6F–4. . . . . . . . . . . . . . . . . . . . . . 
Front Exhaust Pipe and Associated Parts 6F–4. 
Removal 6F–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Installation 6F–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Three Way Catalytic Converter 6F–5. . . . . . . . . . . . 
Removal 6F–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Installation 6F–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust Silencer 6F–6. . . . . . . . . . . . . . . . . . . . . . . . 
Exhaust Silencer and Associated Parts 6F–6. . . 
Removal 6F–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Installation 6F–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Rear Exhaust pipe 6F–7. . . . . . . . . . . . . . . . . . . . . . . 
Rear Exhaust pipe and Associated Parts 6F–7. 
Removal 6F–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Installation 6F–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Main Data and Specifications 6F–8. . . . . . . . . . . . . 
Service Precaution
WARNING: IF  SO  EQUIPPED  WITH  A
SUPPLEMENTAL  RESTRAINT  SYSTEM  (SRS),
REFER  TO  THE  SRS  COMPONENT  AND  WIRING
LOCATION VIEW IN ORDER TO DETERMINE
WHETHER YOU ARE PERFORMING SERVICE ON OR
NEAR  THE  SRS  COMPONENTS  OR  THE  SRS
WIRING.  WHEN  YOU  ARE  PERFORMING  SERVICE
ON OR NEAR THE SRS COMPONENTS OR THE SRS
WIRING,  REFER  TO  THE  SRS  SERVICE
INFORMATION.  FAILURE  TO  FOLLOW  WARNINGS
COULD  RESULT  IN  POSSIBLE  AIR  BAG
DEPLOYMENT,  PERSONAL  INJURY,  OR
OTHERWISE UNNEEDED SRS SYSTEM REPAIRS.
CAUTION: Always  use  the  correct  fastener  in  the
proper  location.  When  you  replace  a  fastener,  use
ONLY  the  exact  part  number  for  that  application.
ISUZU  will  call  out  those  fasteners  that  require  a
replacement  after  removal.  ISUZU  will  also  call  out
the  fasteners  that  require  thread  lockers  or  thread
sealant.  UNLESS  OTHERWISE  SPECIFIED,  do  not
use supplemental coatings (Paints, greases, or other
corrosion  inhibitors)  on  threaded  fasteners  or
fastener  joint  interfaces.  Generally,  such  coatings
adversely  affect  the  fastener  torque  and  the  joint
clamping force, and may damage the fastener. When
you  install  fasteners,  use  the  correct  tightening
sequence  and  specifications.  Following  these
instructions can help you avoid damage to parts and
systems. 
Page 5014 of 6000

6F–3 ENGINE EXHAUST
For Isuzu General Motors (IGM)
150RW058
When  inspecting  or  replacing  exhaust  system
components,  make  sure  there  is  adequate  clearance
from all points on the underbody to prevent overheating
the  floor  pan  and  possible  damage  to  the  passenger
compartment insulation and trim materials.
Check complete exhaust system and nearby body areas
and rear compartment lid for broken, damaged, missing
or  mispositioned  parts,  open  seams,  holes,  loose
connections  or  other  deterioration  which  could  permit
exhaust  fumes  to  seep  into  the  rear  compartment  or
passenger  compartment.  Dust  or  water  in  the  rear
compartment may be an indication of a problem in one of
these  areas.  Any  faulty  areas  should  be  corrected
immediately.
Hangers
Various  types  of  hangers  are  used  to  support  exhaust
system(s).  These  include  conventional  rubber  straps,
rubber rings, and rubber blocks.
The  installation  of  exhaust  system  supports  is  very
important,  as  improperly  installed  supports  can  cause
annoying vibrations which can be difficult to diagnose.
Three Way Catalytic Converter
The three way catalytic converter is an emission control
device added to the exhaust system to reduce pollutants
from the exhaust gas stream.
CAUTION: The catalytic converter requires the use
of unleaded fuel only.
Periodic  maintenance  of  the  exhaust  system  is  not
required.  If  the  vehicle  is  raised  for  other  service,  it  is
advisable to check the condition of the complete exhaust
system.
A  dual  bed  monolith  catalytic  converter  is  used  in
combination with three way catalytic converter.
Catalytic Types:
Three way (Reduction/Oxidation) catalyst
The  catalyst  coating  on  the  three  way  (reduction)
converter  contains  platinum  and  rhodium  which  lowers
the levels of nitrous oxide (NOx) as well as hydrocarbons
(HC) and carbon monoxide (Co).
Gasket
The  gasket  must  be  replaced  whenever  a  new  exhaust
pipe, muffler or catalytic converter is installed. 
Page 5020 of 6000

6G–1 ENGINE LUBRICATION
ENGINE
ENGINE LUBRICATION
CONTENTS
Service Precaution 6G–1. . . . . . . . . . . . . . . . . . . . . . 
General Description 6G–2. . . . . . . . . . . . . . . . . . . . . 
Oil Pump 6G–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Oil Pump and Associated Parts 6G–3. . . . . . . . . . 
Oil Pump and Associated Parts 6G–3. . . . . . . . . . 
Inspection and Repair 6G–4. . . . . . . . . . . . . . . . . . 
Reassembly 6G–5. . . . . . . . . . . . . . . . . . . . . . . . . . 
Oil Pan and Crankcase 6G–7. . . . . . . . . . . . . . . . . . 
Removal 6G–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Installation 6G–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Oil Pump 6G–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removal 6G–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Installation 6G–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Oil Pump Oil Seal 6G–12. . . . . . . . . . . . . . . . . . . . . . . 
Removal 6G–12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Installation 6G–12. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Oil Filter 6G–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Removal 6G–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Installation 6G–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Main Data and Specification 6G–14. . . . . . . . . . . . . . 
Special Tool 6G–15. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Service Precaution
WARNING: IF  SO  EQUIPPED  WITH  A
SUPPLEMENTAL  RESTRAINT  SYSTEM  (SRS),
REFER  TO  THE  SRS  COMPONENT  AND  WIRING
LOCATION VIEW IN ORDER TO DETERMINE
WHETHER YOU ARE PERFORMING SERVICE ON OR
NEAR  THE  SRS  COMPONENTS  OR  THE  SRS
WIRING.  WHEN  YOU  ARE  PERFORMING  SERVICE
ON OR NEAR THE SRS COMPONENTS OR THE SRS
WIRING,  REFER  TO  THE  SRS  SERVICE
INFORMATION.  FAILURE  TO  FOLLOW  WARNINGS
COULD  RESULT  IN  POSSIBLE  AIR  BAG
DEPLOYMENT,  PERSONAL  INJURY,  OR
OTHERWISE UNNEEDED SRS SYSTEM REPAIRS.
CAUTION: Always  use  the  correct  fastener  in  the
proper  location.  When  you  replace  a  fastener,  use
ONLY  the  exact  part  number  for  that  application.
ISUZU  will  call  out  those  fasteners  that  require  a
replacement  after  removal.  ISUZU  will  also  call  out
the  fasteners  that  require  thread  lockers  or  thread
sealant.  UNLESS  OTHERWISE  SPECIFIED,  do  not
use supplemental coatings (Paints, greases, or other
corrosion  inhibitors)  on  threaded  fasteners  or
fastener  joint  interfaces.  Generally,  such  coatings
adversely  affect  the  fastener  torque  and  the  joint
clamping force, and may damage the fastener. When
you  install  fasteners,  use  the  correct  tightening
sequence  and  specifications.  Following  these
instructions can help you avoid damage to parts and
systems. 
Page 5035 of 6000

6H–1 ENGINE SPEED CONTROL SYSTEM
ENGINE
ENGINE SPEED CONTROL SYSTEM
CONTENTS
Service Precaution 6H–1. . . . . . . . . . . . . . . . . . . . . . 
Accelerator Pedal Control Cable 6H–2. . . . . . . . . . 
Removal 6H–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Inspection 6H–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Installation 6H–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Adjustment 6H–2. . . . . . . . . . . . . . . . . . . . . . . . . . . Accelerator Pedal 6H–3. . . . . . . . . . . . . . . . . . . . . . . 
Accelerator Pedal and Associated Parts 6H–3. . 
Removal 6H–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Installation 6H–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Adjustment 6H–3. . . . . . . . . . . . . . . . . . . . . . . . . . . 
Service Precaution
WARNING: IF  SO  EQUIPPED  WITH  A
SUPPLEMENTAL  RESTRAINT  SYSTEM  (SRS),
REFER  TO  THE  SRS  COMPONENT  AND  WIRING
LOCATION VIEW IN ORDER TO DETERMINE
WHETHER YOU ARE PERFORMING SERVICE ON OR
NEAR  THE  SRS  COMPONENTS  OR  THE  SRS
WIRING.  WHEN  YOU  ARE  PERFORMING  SERVICE
ON OR NEAR THE SRS COMPONENTS OR THE SRS
WIRING,  REFER  TO  THE  SRS  SERVICE
INFORMATION.  FAILURE  TO  FOLLOW  WARNINGS
COULD  RESULT  IN  POSSIBLE  AIR  BAG
DEPLOYMENT,  PERSONAL  INJURY,  OR
OTHERWISE UNNEEDED SRS SYSTEM REPAIRS.
CAUTION: Always  use  the  correct  fastener  in  the
proper  location.  When  you  replace  a  fastener,  use
ONLY  the  exact  part  number  for  that  application.
ISUZU  will  call  out  those  fasteners  that  require  a
replacement  after  removal.  ISUZU  will  also  call  out
the  fasteners  that  require  thread  lockers  or  thread
sealant.  UNLESS  OTHERWISE  SPECIFIED,  do  not
use supplemental coatings (Paints, greases, or other
corrosion  inhibitors)  on  threaded  fasteners  or
fastener  joint  interfaces.  Generally,  such  coatings
adversely  affect  the  fastener  torque  and  the  joint
clamping force, and may damage the fastener. When
you  install  fasteners,  use  the  correct  tightening
sequence  and  specifications.  Following  these
instructions can help you avoid damage to parts and
systems.