2004 ISUZU TF SERIES tow

ENGINE MECHANICAL (C24SE) 6A-73




Oxygen Sensor (If applicable)
Removal
1. Remove wiring harness plug.
2. Remove oxygen sensor from the front exhaust pipe.


Tighten (Torque)
Oxygen sensor in exhaust pipe - 30 N

m (3.1 kgf

m)









Throttle Valve Position Sensor
Removal
1. Remove wiring harness connector.
2. Remove throttle valve position sensor.

Installation
1. Install throttle valve position sensor.
2. Install wiring harness connector.


Accelerator Pedal and Cable
Removal
1. Remove pad stopper from pedal stop bolt.





Installation
1. Install pad stopper.

Inspection
Ensure that accelerator pedal is fully in idle position and
accelerator level at engine is in closed position.

Pull outer sleeve of accelerator cable towards pedal and check
that clip on sleeve is in slot nearest to grommet.

Reposition clip if necessary, and check that full throttle and idle
positions are obtained at engine lever.

6D1-4 ENGINE ELECTRICAL

Battery Charging
Observe the following safety precautions when charging the
battery:
1. Never attempt to charge the battery when the fluid level is
below the lower level line on the side of the battery. In this
case, the battery must be replaced.
2. Pay close attention to the battery during charging
procedure.
Battery charging should be discontinued or the rate o
f
charge reduced if the battery feels hot to the touch.
Battery charging should be discontinued or the rate o
f
charge reduced if the battery begins to gas or spew
electrolyte from the vent holes.
3. In order to more easily view the hydrometer blue dot or ring,
it may be necessary to jiggle or tilt the battery.
4. Battery temperature can have a great effect on battery
charging capacity.
5. The sealed battery used on this vehicle may be either quick
charged or slow charged in the same manner as othe
r
batteries.
Whichever method you decide to use, be sure that you
completely charge the battery. Never partially charge the
battery.































Jump Starting
Jump Starting with an Auxiliary (Booster)
Battery
CAUTION: Never push or tow the vehicle in an attempt to
start it. Serious damage to the emission system as well as
other vehicle parts will result.
Treat both the discharged battery and the booster battery
with great care when using jumper cables.
Carefully follow the jump starting procedure, being careful
at all times to avoid sparking.
WARNING: FAILURE TO CAREFULLY FOLLOW THE JUMP
STARTING PROCEDURE COULD RESULT IN THE
FOLLOWING:
1. Serous personal injury, particularly to your eyes.
2. Property damage from a battery explosion, battery acid, o
r
an electrical fire.
3. Damage to the electronic components of one or both
vehicles particularly.
Never expose the battery to an open flame or electrical spark.
Gas generated by the battery may catch fire or explode.
Remove any rings, watches, or other jewelry before working
around the battery. Protect your eyes by wearing an approved
set of goggles.
Never allow battery fluid to come in contact with your eyes or
skin.
Never allow battery fluid to come in contact with fabrics or
painted surfaces.

6D3-18 STARTING AND CHARGING SYSTEM
Reassembly
Generator
(a) Press new bearing onto slipring end of the rotor taking care
to aplly the force to the bearing inner race only, otherwise
the bearing will be noisy and it's life will be shortened.
(b) Fit a new bearing to the drive end housing, fit the bearing
plate, and four retaining screws, press the rotor into the
bearing, using a support tool to take the thrust against the
bearing inner.
The support is fitted from the pulley side of the bearing. In
this way the thrust is not taken by the drive end housing.
(c) To fit pulley, mount an 8mm Allen key in the vice with the
short end upwards, place a 24mm ring spanner on the shaft
nut, position the internal hexagon of the rotor shaft onto the
Allen key, tighten the nut to the required torque(See torque
chart)
(d) Inspect the bearing support ring for signs of damage, if in
doubt replace the ring by pressing it into the housing by
hand, do not use excessive force.
(e) To refit the rectifier, fit new mica washers to the positive
heatsink B+ bolt and retaining screw each washer must
have heatsink compound applied to both surfaces before
fitting.
Fit the three retaining screws to the rectifier then install into
slipring end housing. Tighten the B+ bolt to the reuired
torque.
(f) To refit the stator, make sure the spigot surface are clean
and free from damage, fit the stator into the slipring end
housing noting the correct lead connection positioning. Fit
the stator leads into the wire loops in the recrifier. Using a
pair of pliers squeeze the loop to retain the stator lead prior
to soldering. Repeat for each lead in turn, solder the leads
into position using 60/40 resin cored solder. Make sure the
leads will be clear of the internal fan when the rotor is
assmebled into the stator.
(g) Carefully install the rotor into the stator/slipring end housing
assembly, noting the alignment of the housings and through
bolt holes. Fit the through bolts making sure the stator is
seated correctly, tighten the through bolts to the correct
torque setting (uneven torque can produce magnetic noise
levels above normal).
(h) Fitting the regulator. Compress the brushes into the brush
holder by hand, slip the regulator through the opening in the
rear of the slipring end housing until the brushes come in
contact with the slipring. Press the regulator towards the
slipring until the holes are aligned then fit the retaining
screws and tighten.

6E–98 ENGINE DRIVEABILITY AND EMISSIONS
FUEL METERING SYSTEM CHECK
Some failures of the fuel metering system will result in
an “Engine Cranks But Will Not Run” symptom. If this
condition ex ists, refer to the Cranks But Will Not Run
chart. This chart will determine if the problem is caused
by the ignition system, the ECM, or the fuel pump
electrical circuit.
Refer to Fuel System Electrical Test for the fuel system
wiring schematic.
If there is a fuel delivery problem, refer to Fuel System
Diagnosis, which diagnoses the fuel injectors, the fuel
pressure regulator, and the fuel pump.
Followings are applicable to the vehicles with
closed Loop System:
If a malfunction occurs in the fuel metering system, it
usually results in either a rich HO2S signal or a lean
HO2S signal. This condition is indicated by the HO2S
voltage, which causes the ECM to change the fuel
calculation (fuel injector pulse width) based on the
HO2S reading. Changes made to the fuel calculation
will be indicated by a change in the long term fuel trim
values which can be monitored with a Scan Tool. Ideal
long term fuel trim values are around 0%; for a lean
HO2S signal, the ECM will add fuel, resulting in a fuel
trim value above 0%. Some variations in fuel trim values
are normal because all engines are not ex actly the
same. If the evaporative emission canister purge is 02
status may be rich condition. 02 status indicates the
lean condition, refer to DTC P1171 for items which can
cause a lean HO2S signal.
FUEL INJECTOR COIL TEST PROCEDURE
AND FUEL INJECTOR BALANCE TEST
PROCEDURE
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart:
2. Relieve the fuel pressure by connecting 5-8840-
0378-0 T-Joint to the fuel pressure connection on the
fuel rail.
Caution: In order to reduce the risk of fire and
personal injury, wrap a shop towel around the
fuel pressure connection. The towel will absorb
any fuel leakage that occurs during the
connection of the fuel pressure gauge. Place the
towel in an approved container when the
connection of the fuel pressure gauge is
complete.
Place the fuel pressure gauge bleed hose in an
approved gasoline container.
With the ignition switch OFF open the valve on the
fuel pressure gauge.
3. Record the lowest voltage displayed by the DVM
after the first second of the test. (During the first
second, voltage displayed by the DVM may be
inaccurate due to the initial current surge.)
Injector Specifications:
The voltage displayed by the DVM should be
within the specified range.
The voltage displayed by the DVM may increase
throughout the test as the fuel injector windings
warm and the resistance of the fuel injector
windings changes.Resistance OhmsVoltage Specification at
10°C-35°C (50°F-95°F)
11.8-12.6 5.7-6.6

ENGINE DRIVEABILITY AND EMISSIONS 6E–101
5 1. Set the Injector Adapter Cable to injector #1.
2. Press the “Push to Start Test” button on the fuel
injector tester.
3. Observe the voltage reading on the DVM.
Important: The voltage reading may rise during the
test.
4. Record the lowest voltage observed after the first
second of the test.
5. Set the Injector Adapter Cable to the nex t injector
and repeat steps 2, 3, and 4.
Did any fuel injector have an erratic voltage reading
(large fluctuations in voltage that did not stabilize) or a
voltage reading above the specified value? 9.5V Go to Step 4Go to Step 6
6 1. Identify the highest voltage reading recorded
(other than those above 9.5V).
2. Subtract the voltage reading of each injector from
the highest voltage selected in step 1. Repeat until
you have a subtracted value for each injector.
For any injector, is the subtracted value in step 2
greater than the specified value? 0.6V Go to Step 4Go to Step 7
7Caution: In order to reduce the risk of fire and
personal injury, wrap a shop towel around the fuel
pressure connection. The towel will absorb any
fuel leakage that occurs during the connection of
the fuel pressure gauge. Place the Towel in an
approved container when the connection of the
fuel pressure gauge is complete.
1. Connect the 5-8840-0378-0 Fuel Pressure Gauge
to the fuel pressure test port.
2. Energize the fuel pump using the Scan Tool.
3. Place the bleed hose of the fuel pressure gauge
into an approved gasoline container.
4. Bleed the air out of the fuel pressure gauge.
5. With the fuel pump running, observe the reading
on the fuel pressure gauge.
Is the fuel pressure within the specified values?296kPa-
376kPa
(43-55psi) Go to Step 8Go to Fuel
System
Diagnosis
8 Turn the fuel pump OFF.
Does the fuel pressure remain constant?
—Go to Step 9Go to Fuel
System
Diagnosis Step Action Value(s) Yes No

ENGINE DRIVEABILITY AND EMISSIONS 6E–103
FUEL SYSTEM ELECTRICAL TEST
Circuit Description
When the ignition switch is first turned ON, the engine
control module (ECM) energizes the fuel pump relay
which applies power to the in-tank fuel pump. The fuel
pump relay will remain ON as long as the engine is
running or cranking and the ECM is receiving 58X
crankshaft position pulses. If no 58X crankshaft position
pulses are present, the ECM de-energizes the fuel
pump relay within 2 seconds after the ignition is turned
ON or the engine is stopped.
The fuel pump delivers fuel to the fuel rail and injectors,
then to the fuel pressure regulator. The fuel pressure
regulator controls fuel pressure by allowing ex cess fuel
to be returned to the fuel tank. With the engine stopped
and ignition ON, the fuel pump can be turned ON by
using a command by the scan tool.
Diagnostic Aids
An intermittent may be caused by a poor connection,
rubbed-through wire insulation, or a wire broken inside
the insulation. Check for the following items:
Poor connection or damaged harness - Inspect the
ECM harness and connectors for improper mating,
broken locks, improperly formed or damaged
terminals, poor terminal-to-wire connection, and
damaged harness.
Caution: To reduce the risk of fire and personal
injury:
It is necessary to relieve fuel system pressure
before connecting a fuel pressure gauge.
Refer to Fuel Pressure Relief Procedure,
below.
A small amount of fuel may be released when
disconnecting the fuel lines. Cover fuel line
fittings with a shop towel before
disconnecting, to catch any fuel that may leak
out. Place the towel in an approved container
when the disconnect is completed.

6E–108 ENGINE DRIVEABILITY AND EMISSIONS
FUEL SYSTEM DIAGNOSIS
Circuit Description
When the ignition switch is turned ON, the engine
control module (ECM) will turn ON the in-tank fuel
pump. The in-tank fuel pump will remain ON as long as
the engine is cranking or running and the ECM is
receiving 58X crankshaft position pulses. If there are no
58X crankshaft position pulses, the ECM will turn the in-
tank fuel pump OFF 2 seconds after the ignition switch
is turned ON or 2 seconds after the engine stops
running.
The in-tank fuel pump is an electric pump within an
integral reservoir. The in-tank fuel pump supplies fuel
through an in-line fuel filter to the fuel rail assembly. The
fuel pump is designed to provide fuel at a pressure
above the pressure needed by the fuel injectors. A fuel
pressure regulator, attached to the fuel rail, keeps the
fuel available to the fuel injectors at a regulated
pressure. Unused fuel is returned to the fuel tank by a
separate fuel return line.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Connect the fuel pressure gauge to the fuel feed line
as shown in the fuel system illustration. Wrap a shop
towel around the fuel pressure connection in order to
absorb any duel leakage that may occur when
installing the fuel pressure gauge. With the ignition
switch ON and the fuel pump running, the fuel
pressure indicated by the fuel pressure gauge
should be 283-376 kPa (41-55 psi). This pressure is
controlled by the amount of pressure the spring
inside the fuel pressure regulator can provide.
3. A fuel system that cannot maintain a constant fuel
pressure has a leak in one or more of the following
areas:
The fuel pump check valve.
The fuel pump flex line.
The valve or valve seat within the fuel pressure
regulator.

ENGINE DRIVEABILITY AND EMISSIONS 6E–109
The fuel injector(s).
4. Fuel pressure that drops off during acceleration,
cruise, or hard cornering may case a lean condition.
A lean condition can cause a loss of power, surging,
or misfire. A lean condition can be diagnosed using a
Tech 2 Scan Tool.
Following are applicable to the vehicle with
closed Loop System:
If an ex tremely lean condition occurs, the ox ygen
sensor(s) will stop toggling. The ox ygen sensor
output voltage(s) will drop below 500 mV. Also, the
fuel injector pulse width will increase.
Important: Make sure the fuel system is not
operating in the “Fuel Cut-Off Mode.”
When the engine is at idle, the manifold pressure is
low (high vacuum). This low pressure (high vacuum)
is applied to the fuel pressure regulator diaphragm.
The low pressure (high vacuum) will offset the
pressure being applied to the fuel pressure regulator
diaphragm by the spring inside the fuel pressure
regulator. When this happens, the result is lower fuel
pressure. The fuel pressure at idle will vary slightly
as the barometric pressure changes, but the fuel
pressure at idle should always be less than the fuel
pressure noted in step 2 with the engine OFF.
16.Check the spark plug associated with a particular
fuel injector for fouling or saturation in order to
determine if that particular fuel injector is leaking. If
checking the spark plug associated with a particular
fuel injector for fouling or saturation does not
determine that a particular fuel injector is leaking,
use the following procedure:
Remove the fuel rail, but leave the fuel lines and
injectors connected to the fuel rail. Refer to Fuel
Rail Assembly in On-Vehicle Service.
Lift the fuel rail just enough to leave the fuel
injector nozzles in the fuel injector ports.
Caution: In order to reduce the risk of fire and
personal injury that may result from fuel
spraying on the engine, verify that the fuel rail is
positioned over the fuel injector ports and verify
that the fuel injector retaining clips are intact.
Pressurize the fuel system by connecting a 20
amp fused jumper between B+ and the fuel
pump relay connector.
Visually and physically inspect the fuel
injector nozzles for leaks.
17.A rich condition may result from the fuel pressure
being above 376 kPa (55 psi). A rich condition may
cause a 45 to set. Driveability conditions associatedwith rich conditions can include hard starting
(followed by black smoke) and a strong sulfur smell
in the ex haust.
20.This test determines if the high fuel pressure is due
to a restricted fuel return line or if the high fuel
pressure is due to a faulty fuel pressure regulator.
21.A lean condition may result from fuel pressure below
333 kPa (48 psi). A lean condition may cause a 44 to
set. Driveability conditions associated with lean
conditions can include hard starting (when the
engine is cold), hesitation, poor driveability, lack of
power, surging, and misfiring.
22.Restricting the fuel return line causes the fuel
pressure to rise above the regulated fuel pressure.
Command the fuel pump ON with the scan tool. The
fuel pressure should rise above 376 kPa (55 psi) as
the fuel return line becomes partially closed.
NOTE: Do not allow the fuel pressure to exceed 414
kPa (60 psi). Fuel pressure in excess of 414 kPa (60
psi) may damage the fuel pressure regulator.
Caution: To reduce the risk of fire and personal
injury:
It is necessary to relieve fuel system pressure
before connecting a fuel pressure gauge.
Refer to Fuel Pressure Relief Procedure,
below.
A small amount of fuel may be released when
disconnecting the fuel lines. Cover fuel line
fittings with a shop towel before
disconnecting, to catch any fuel that may leak
out. Place the towel in an approved container
when the disconnect is completed.
Fuel Pressure Relief Procedure
1. Remove the fuel cap.
2. Located on the intake manifold which is at the top
right part of the engine.
3. Start the engine and allow it to stall.
4. Crank the engine for an additional 3 seconds.
Fuel Pressure Gauge Installation
1. Remove the fuel pressure fitting cap.
2. Install fuel pressure gauge 5-8840-0378-0 to the
fuel feed line located on the upper right side of the
engine.
3. Reinstall the fuel pump relay.