catalytic converter ISUZU TF SERIES 2004 Owner's Manual

6F-4 ENGINE EXHAUST (6VE1 3.5L)
Three Way Catalytic Converter and Center Exhaust Pipe
Three Way Catalytic Converter and Center Exhaust Pipe and Associated Parts



RTW46FMF000201
Legend (4) Three Way Catalytic Converter LH
(1) Front Exhaust Pipe Fixing Nuts (5) Mounting Rubber
(2) O
2 Sensor (6) Exhaust Pipe Fixing Nuts
(3) Three Way Catalytic Converter RH (7) Center Exhaust Pipe


Removal
1. Disconnect battery ground cable.
2. Lift up the vehicle and support with suitable safety
stands.
3. Disconnect O
2 sensor harness connectors (2).
4. Remove the center exhaust pipe fixing nuts (6) and
the exhaust silencer fixing bolts, then remove the
center exhaust pipe and the mounting rubber.
5. Remove the front exhaust pipe fixing nuts (1) and
the mounting rubber, then remove the three way
catalytic converter (3) (4).
Installation
1. Install the three way catalytic converter (3) (4) and
the mounting rubber, and tighten the fixing nuts (1)
to the specified torque.
Torque : 67 N




m (6.8 kg




m/49 lb ft)
2. Install the center exhaust pipe and the mounting
rubbler, and tighten the fixing nuts (6) and bolts to
the specified torque.
Torque : 43 N




m (4.4 kg




m/32 lb ft)
3. Connect the O
2 sensor connectors (2).

ENGINE MECHANICAL (C24SE) 6A-77

Cooling System
Radiator

Type: Cross-flow

Radiator core surface in cm
2: 2000

Cooling system capacity (in litres): 7.2



Anti-freeze Mixture
Anti-freeze Mixture

Required
Quantity Up to-10




C
Quantity in litres Up to-20




C
Quantity in litres Up to-30




C
Quantity in litres Up to-40




C
Quantity of litres
(in litres) Water
(80%) Anti-
Freeze
(20%) Water
(66%) Anti-
Freeze
(34%) Water
(56%) Anti-
Freeze
(44%) Water
(48%) Anti-
Freeze
(52%)
7.2 5.7 1.5 4.7 2.5 4.0 3.2 3.4 3.8



Cooling System (continued)
Fan

Type Visco Clutch Fan
Number of blades 5
Distribution of blades asymmetric
Diameter mm



Radiator cap

Boiling point 123
C
Opening pressure kPa (bar) 120 to 135 (1.20 to 1.35)



Thermostat

Start of opening 92
C
Fully opened 107
C
Type Bypassed



Idle Speeds, CO Content, Ignition
Adjustment

Applicable System Idle speed in min-1 (rpm)
Manual CO content
in vol. % Ignition timing in CA BTDC (adjustment
ensues at able speed,
ignition marks must align) with TDC
sensor measuring instrument:
Closed Loop System 825 *<0.4 *** 8 to 12
Open Loop System 825
**1.0+0.2
-0.5 *** 8 to 12
Note) * CO content adjustment not applicable.
** CO content adjustment refer to Section 6E1 (W/O catalytic converter system)
*** Ignition timing adjustment not possible.

6E–52 ENGINE DRIVEABILITY AND EMISSIONS
GENERAL DESCRIPTION FOR FUEL
METERING
The fuel metering system starts with the fuel in the fuel
tank. An electric fuel pump, located in the fuel tank,
pumps fuel to the fuel rail through an in-line fuel filter.
The pump is designed to provide fuel at a pressure
above the pressure needed by the injectors.
A fuel pressure regulator in the fuel rail keeps fuel
available to the fuel injectors at a constant pressure.
A return line delivers unused fuel back to the fuel tank.
The basic function of the air/fuel metering system is to
control the air/fuel delivery to the engine. Fuel is
delivered to the engine by individual fuel injectors
mounted in the intake manifold.
The main control sensor is the heated ox ygen sensor
located in the ex haust system. The heated ox ygen
sensor reports to the ECM how much oxygen is in the
ex haust gas. The ECM changes the air/fuel ratio to the
engine by controlling the amount of time that fuel
injector is “On”.
The best mix ture to minimize exhaust emissions is 14.7
parts of air to 1 part of gasoline by weight, which allows
the catalytic converter to operate most efficiently.
Because of the constant measuring and adjusting of the
air/fuel ratio, the fuel injection system is called a “closed
loop” system.
The ECM monitors signals from several sensors in
order to determine the fuel needs of the engine. Fuel is
delivered under one of several conditions called “mode”.
All modes are controlled by the ECM.
Battery Voltage Correction Mode
When battery voltage is low, the ECM will compensate
for the weak spark by increasing the following:
The amount of fuel delivered.
The idle RPM.
Clear Flood Mode
Clear a flooded engine by pushing the accelerator pedal
down all the way. The ECM then de-energizes the fuel
injectors. The ECM holds the fuel injectors de-energized
as long as the throttle remains above 75% and the
engine speed is below 800 RPM. If the throttle position
becomes less than 75%, the ECM again begins to pulse
the injectors ON and OFF, allowing fuel into the
cylinders.
Deceleration Fuel Cutoff (DFCO) Mode
The ECM reduces the amount of fuel injected when it
detects a decrease in the throttle position and the air
flow. When deceleration is very fast, the ECM may cut
off fuel completely. Until enable conditions meet the
engine revolution less 1000 rpm or manifold absolute
pressure less than 10 kPa.
Engine Speed/ Vehicle Speed/ Fuel Disable
Mode
The ECM monitors engine speed. It turns off the fuel
injectors when the engine speed increases above 6000
RPM. The fuel injectors are turned back on when
engine speed decreases below 3500 RPM.
Acceleration Mode
The ECM provides ex tra fuel when it detects a rapid
increase in the throttle position and the air flow.
Fuel Cutoff Mode
No fuel is delivered by the fuel injectors when the
ignition is OFF. This prevents engine run-on. In addition,
the ECM suspends fuel delivery if no reference pulses
are detected (engine not running) to prevent engine
flooding.
Starting Mode
When the ignition is first turned ON, the ECM energizes
the fuel pump relay for two seconds to allow the fuel
pump to build up pressure. The ECM then checks the
engine coolant temperature (ECT) sensor and the
throttle position sensor to determine the proper air/fuel
ratio for starting.
The ECM controls the amount of fuel delivered in the
starting mode by adjusting how long the fuel injectors
are energized by pulsing the injectors for very short
times.
Run Mode
The run mode has the following two conditions:
Open loop
Closed loop
When the engine is first started, the system is in “open
loop” operation. In “Open Loop,” the ECM ignores the
signal from the heated oxygen sensor (HO2S). It
calculates the air/fuel ratio based on inputs from the TP,
ECT, and MAP sensors.
The system remains in “Open Loop” until the following
conditions are met:
The HO2S has a varying voltage output showing that
it is hot enough to operate properly (this depends on
temperature).
The ECT has reached a specified temperature.
A specific amount of time has elapsed since starting
the engine.
Engine speed has been greater than a specified RPM
since start-up.
The specific values for the above conditions vary with
different engines and are stored in the programmable
read only memory (PROM). When these conditions are
met, the system enters “closed loop” operation. In
“closed loop,” the ECM calculates the air/fuel ratio
(injector on-time) based on the signal from the HO2S.
This allows the air/fuel ratio to stay very close to 14.7:1.

6E–258 ENGINE DRIVEABILITY AND EMISSIONS
EXCESSIVE EXHAUST EMISSIONS OR ODORS SYMPTOM
DEFINITIONS: Vehicle fails an emission test. There is ex cessive “rotten egg” smell. (Ex cessive odors do not
necessarily indicate ex cessive emissions.)
Step Action Value(s) Yes No
1Was the “On-Board Diagnostic (OBD) System Check”
performed?—Go to Step 2Go to OBD
System Check
2 1. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?—Verify repair Go to Step 3
3 Was a visual/physical check performed?
—Go to Step 4Go to Visual /
physical Check.
4 Does the customer continual accelerate On/Off during
cold condition?—System OK Go to Step 5
5 Is the customer using the incorrect fuel type?
—Replace with
unleaded fuel Go to Step 6
6 Check for vacuum leaks (vacuum lines, intake
manifold, throttle body, etc.)
Were any vacuum leaks found?—Go to Step 17Go to Step 7
7 1. Check fuel cap for proper installation.
2. Secure the fuel cap if necessary.
Was a problem found?—Go to Step 17Go to Step 8
8 Check the fuel pressure. Refer to 6E-108 page “Fuel
System Diagnosis” .
Was a problem found?—Go to Step 17Go to Step 9
9 1. Check for faulty, plugged or incorrectly installed
PCV valve.
2. Verify that the PCV system is not plugged.
Was a problem found? —Go to Step 17Go to Step 10
10 Check the injector connectors, if any of the injectors
are connected to an incorrect cylinder, correct as
necessary.
Was a problem found?—Go to Step 17Go to Step 11
11 Perform the
Injector Coil/Balance Test
(Refer to 6E-
98 page).
Was a problem found.—Go to Step 17Go to Step 12
12 Check for a problem with the engine cooling system.
Was a problem found?—Go to Step 17Go to Step 13
13 Check EVAP canister for fuel loading. Refer to
Evaporative Emission Control System.
Was a problem found?—Go to Step 17Go to Step 14
14 Check the EVAP purge solenoid valve operation.
Is the valve operated normally?—Go to Step 17Veri fy repai r &
Go to Step 15
15 Check the ex haust system for a possible restriction:
Damaged or collapsed pipes
Internal catalytic converter failure
Was a problem found?—Verify repair &
Go to Step 16Go to Step 17

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

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.

ENGINE EXHAUST 6F-5
Exhaust Pipe
Exhaust Pipe and Associated parts





RTW46FLF000401













Removal
(2.4L)
CAUTION
When you remove or install the front exhaust pipe, make
sure not to damage the fuel evaporative pipe.
1. Damper rubber
2. Exhaust silencer
3. Mid pipe
4. Damper rubber
5. Front exhaust pipe fixing nut
6. Catalytic converter (If applicable)
7. Front exhaust pipe

6F-6 ENGINE EXHAUST


Installation
To install, follow the removal steps in the reverse order.










Important - Installation
1. Front Exhaust Pipe Flange Nut
Connect the exhaust pipe to the exhaust manifold.
Front exhaust pipe to manifold nut.
Torque

N
m (kgf
m)
28 (2.9)
Inspection
Make the necessary adjustments, and part replacements if
excessive wear or damage is discover during inspection.

1. Front Exhaust Pipe
2. Center Exhaust Pipe and Catalytic Converter Flange Nut
3. Exhaust Pipe Damper Rubber
4. Exhaust Silencer with Rear Exhaust Pipe

Check the pipes for for corrosion, cracking , damage or
misalignment and repair if required.
Check the damper rubber for deterioration or damage and
repair if required.

ENGINE EXHAUST 6F-7
Front Exhaust Pipe (W/O Catalytic
Converter)
Front Exhaust Pipe and Associated Parts





RTW46F000101
Legend
1. Front Exhaust Pipe Fixing Nuts
2. Front Exhaust Pipe
3. Mid Exhaust Pipe Fixing Nuts










Removal
(2.4L)
1. Disconnect battery ground cable.
2. Raise the vehicle and support with suitable safety stands.
3. Remove the front exhaust pipe fixing nuts (1).
4. Remove mid pipe fixing nuts (3).
5. Remove front exhaust pipe (2).




Installation
1. Install front exhaust pipe (2) and tighten four nuts (1).
Torque:
Nuts: 28 N




m (2.9 kgf




m)
2. Tighten two nuts (3).
Torque: 43 N




m (4.4 kgf




m)

ENGINE EXHAUST 6F-9
Catalytic Converter (If applicable)
Catalytic Converter and Associated Parts





RTW46FSF000301
Legend
1. Catalytic Converter
2. O
2 Sensor Converter
3. Front Pipe Fixing Nuts
4. Mid Pipe Fixing Nuts








Removal
(2.4L)
1. Disconnect battery ground cable.
2. Raise the vehicle and support with suitable safety stands.
3. Remove front pipe fixing nuts (3).
4. Remove mid pipe fixing nuts (4).
5. Remove the O
2 sensor connector (2).
6. Remove the front exhaust pipe with catalytic converter (1).





Installation
1. Install Catalytic Converter (1) and tighten four to the
specified torque:
Torque:
Fixing nuts: 28 N




m (2.9 kgf




m)
2. Tight two nuts (4)
Torque:
Nuts: 43 N




m (4.4 kgf




m)
3. Connect the O
2 sensor connector (2).