ISUZU TF SERIES 2004 Workshop Manual

ENGINE DRIVEABILITY AND EMISSIONS 6E–275
IGNITION COIL
Location
Back of the engine right-hand side.
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the ignition coil connector.
3. Disconnect four spark plug cables from the ignition
coil.
4. Loosen three bolts and remove ignition coil from the
bracket.
Installation Procedure
1. Tighten the ignition coil by three bolts.
2. Connect four spark plug cables to the ignition coil.
3. Connect a ignition coil connector to the ignition coil.
4. Connect the negative battery cable.
NOTE: Verify any DTCs (diagnosis Trouble Code) are
not stored after replacement.
Verify proper connection of spark plug cables for each
cylinders.
SPARK PLUGS
Location
Installed on the left-hand side of cylinder head.
Removal Procedure
1. Disconnect the negative battery cable
2. Remove the spark plug cable.
3. Remove the spark plug.
Inspection
1. Check the insulator for cracks. Replace the spark
plug if cracks are present.
2. Check the electrode condition and replace the spark
plug if necessary.
If the spark plug electrodes and insulators are fouled
with carbon or oil, the engine will not operate efficiently.
There are a number of possible causes:
Fuel mix ture is too rich.

6E–276 ENGINE DRIVEABILITY AND EMISSIONS
Oil in the combustion chamber.
The spark plug gap is not set correctly.
If spark plug fouling is ex cessive, check the fuel and al
system for possible causes of trouble. If fuel and al
system are normal, install spark plugs of a higher heat
range which have the same physical dimensions as the
original equipment spark plugs.
The following symptoms are characteristics of spark
plugs that are running too hot:
Fuel mixture is too lean.
Heat range is incorrect.
If vehicle usage does not conform to normal driving
conditions, a more suitable spark plug may be
substituted.
If fuel and al system are normal, in most cases of this
sort, the problem can be corrected by using a colder
type spark plug with the same physical dimensions as
the original equipment spark plug.
3. Check the gaskets for damage and replace if
necessary.
4. Measure the spark plug gap. The specification is 1.0
to 1.1mm (0.039 to 0.043").
5. Adjust the spark gap by bending the grounded
electrode.Installation
1. Tighten the spark plug to the 25N·m (2.5kgf·m).
2. Push the spark plug cable in until it snaps in.
Installation Procedure
1. Install the spark plug to the cylinder head.
2. Tighten the spark plug with specified tightening
torque.
Tightening Torque
Bolt: 25N·m (2.5kgf·m)
3. Connect the spark plug cable to the spark plug.
4. Connect the negative battery cable.
NOTE: Verify any DTCs (diagnosis Trouble Code) are
not stored after replacement.
Verify proper connection of spark plug cables for each
cylinders.

ENGINE DRIVEABILITY AND EMISSIONS 6E–277
SPARK PLUG CABLES
The cable contains a synthetic conductor which is easily
damaged. Never stretch or kink the cable. Disconnect
the cable from spark plug and the ignition coil.
The original equipment cables and the ignition coil are
marked to show correct location of the cables. If spark
plug cables or the ignition coil are replaced previously,
before cables are removed from the ignition coil, mark
the cables and the coil so they can be reconnected in
the same position.
Inspection
NOTE: Never puncture the spark plug cable’s insulation
with a needle or the pointed end of a probe into the
cable. An increase in resistance would be created which
would cause the cable to become defective.
1. If the cable has broken or cracked insulation, it must
be replaced.
2. If the terminals are corroded or loose, the cable
must be replaced.
3. Check that the cable resistance does not ex ceed
specified value.
#1 cylinder: 3.50k
- 5.24k

#2 cylinder: 2.89k
- 4.33k

#3 cylinder: 2.49k
- 3.73k

#4 cylinder: 2.22k
- 3.32k

EMISSION CONTROL ;




CO ADJUSTER (W/
O CATALYSTIC CONVERTER)
CO : Carbon monox ide
Location
Under the leht-hand side of the front sheet.
Removal Procedure
1. Remove the left-hand side of the front sheet. Refer
to Sec.10 CAB “Front Sheet”.
2. Disconnect the CO adjuster connector.
3. Remove the CO adjuster.
Installation Procedure
1. Connect the CO adjuster connector.
2. Install the left-hand side of the front sheet. Refer to
Sec.10 CAB “Front Sheet”.
3. Check and adjust CO concentration.
Checking procedure
1. Operate the engine at normal temperature.
2. Turn all accessories switch OFF.
3. Place the select lever in the “N” range.
4. Start the engine at idle.

6E–278 ENGINE DRIVEABILITY AND EMISSIONS
5. Measure the CO concentration for 1-3 minutes, after
idlling the engine to allow the CO concentration to
stabilize.
6. Check the CO concentration.
7. If the value is not within specification, adjust the CO
concentration.A djustment Procedure
1. Warm-up the engine.
2. Turn OFF switches of all electrical equipment.
3. Open the CO adjuster cap.
4. Turn the CO adjuster screw checking the CO
concentration
.
5. Adjust the CO concentration within specification.
Specification:
CO concentration : 0.6 1.0 %
NOTE: Apply the liquid gasket to the CO adjuster screw
after the adjustment.

ENGINE DRIVEABILITY AND EMISSIONS 6E–279
SPECIAL SERVICE TOOLS
ILLUSTRATION TOOL NO.
TOLL NAME
5-8840-0285-0
(J 39200)
High Impedance
Multimeter
(Digital Voltmeter -DVM)
(1) PCMCIA Card
(2) RS232 Loop Back
Connector
(3) SAE 16/19 Adapter
(4) DLC Cable
(5) TECH 2
5-8840-0385-0
(J 35616-A /BT-8637)
Connector Test Adapter Kit
5-8840-0378-0
(J34730-E)
Port Fuel Injection
Diagnostic Kit
Breaker Box
5-8840-2589-0
Injector Adapter Cable

MEMO

ENGINE EXHAUST 6F-1
SECTION 6F
ENGINE EXHAUST
CONTENTS
PAGE
General Description........................................................................................................ 6F- 2
Service Precaution ......................................................................................................... 6F- 4
Exhaust Pipe ................................................................................................................... 6F- 5
Exhaust pipe and Associated parts.......................................................................... 6F- 5
Removal ...................................................................................................................... 6F- 5
Installation .................................................................................................................. 6F- 6
Inspection ................................................................................................................... 6F- 6
Front Exhaust Pipe ......................................................................................................... 6F- 7
Front Exhaust Pipe and Associated Parts ............................................................... 6F- 7
Removal ...................................................................................................................... 6F- 7
Installation .................................................................................................................. 6F- 7
Mid Pipe ........................................................................................................................... 6F- 8
Mid Pipe and associated Parts ................................................................................. 6F- 8
Removal ...................................................................................................................... 6F- 8
Installation .................................................................................................................. 6F- 8
Catalytic Converter (If applicable) ................................................................................. 6F- 9
Catalytic Converter and Associated Parts ............................................................... 6F- 9
Removal ...................................................................................................................... 6F- 9
Installation .................................................................................................................. 6F- 9
3 way Catalytic Converter System ............................................................................ 6F- 10
Exhaust Silencer ............................................................................................................. 6F- 12
Exhaust Silencer and Associated Parts ................................................................... 6F- 12
Removal ...................................................................................................................... 6F- 12
Installation .................................................................................................................. 6F- 13
Main Data and Specifications ........................................................................................ 6F- 14
Torque Specification.................................................................................................. 6F- 15

6F-2 ENGINE EXHAUST
General Description





RTW46AMF000501

ENGINE EXHAUST 6F-3





























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 (If applicable)
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.

6F-4 ENGINE EXHAUST


Service Precaution
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.