2004 ISUZU TF SERIES change time

ENGINE FUEL (6VE1 3.5L) 6C-3
Fuel Metering
The Engine Control Module (ECM) is in complete
control of this fuel delivery system during normal driving
conditions.
The intake manifold function, like that of a diesel, is
used only to let air into the engine. The fuel is injected
by separate injectors that are mounted over the intake
manifold.
The Barometric Pressure (BARO) sensor measures the
changes in the barometric pressure which result from
engine load and speed changes, which the BARO
sensor converts to a voltage output.
This sensor generates the voltage to change
corresponding to the flow of the air drawn into the
engine.
The changing voltage is transformed into an electric
signal and provided to the ECM.
With receipt of the signals sent from the BARO sensor,
Intake Air Temperature sensor and others, the ECM
determines an appropriate fuel injection pulse width
feeding such information to the fuel injector valves to
effect an appropriate air/fuel ratio.
The Multiport Fuel Injection system utilizes an injection
system where the injectors turn on at every crankshaf
t
revolution. The ECM controls the injector on time so
that the correct amount of fuel is metered depending on
driving conditions.
Two interchangeable “O" rings are used on the injecto
r
that must be replaced when the injectors are removed.
The fuel rail is attached to the top of the intake manifold
and supplies fuel to all the injectors.
Fuel is recirculated through the rail continually while the
engine is running. This removes air and vapors from the
fuel as well as keeping the fuel cool during hot weathe
r
operation.
The fuel pressure control valve that is mounted on the
fuel rail maintains a pressure differential across the
injectors under all operating conditions. It is
accomplished by controlling the amount of fuel that is
recirculated back to the fuel tank based on engine
demand.
See Section “Driveability and Emission" for more
information and diagnosis.

STARTING AND CHARGING SYSTEM (6VE1 3.5L) 6D3-21
Stator Coil
1. Measure resistance between respective phases.
2. Measure insulation resistance between stator coil
and core with a mega–ohmmeter.
If less than standard, replace the coil.





066RS018
Brush
Measure the brush length.
If more than limit, replace the brush.
Standard: 10.mm (0.4134 in)
Limit: 8.4.mm (0.3307 in)






066RS019

Rectifier Assembly
Check for continuity across “P" and “E" in the
100W
range of multimeter.





066RW002
Change polarity, and make sure that there is continuity
in one direction, and not in the reverse direction. In case
of continuity in both directions, replace the rectifie
r
assembly.
IC Regulator Assembly
Check for continuity across “B" and “F" in the
100W
range of multimeter.




066RS021
Change polarity, and make sure that there is continuity
in one direction, and not in the reverse direction. In case
of continuity in both directions, replace the IC regulato
r
assembly.

6E-54 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Crankshaft Position (CKP) Sensor





The crankshaft position (CKP) sensor, which sends a
signal necessary for deciding on injection timing to the
ECM, is mounted on the right-hand side of the cylinde
r
block.
The crankshaft has a 58 teeth press-fit timing disc, from
which the CKP sensor reads the position of the
crankshaft at all the times. It converts this to an
electrical signal, which it sends to the ECM.
Of the 58 teeth, 57 have a base with of 3°, and are
evenly spaced, but tooth No. 58 is 15° wide at its based
to serve as a timing mark, allowing the sensor to repor
t
the standard crankshaft position.
Using the 58 X signals per rotation and the timing-mark
signal sent by the CKP sensor, the ECM is able to
accurately calculate engine speed and crank position.
Also, the position of each cylinder is precisely known by
the ECM from signals sent by the camshaft position
(CMP) sensor, so the sequential multi-point fuel
injection can be controlled with accuracy.

The 58 X signals are converted by the ECM into a
retangle wave signal. This converted signal is sent from
the ECM terminal B12 to the tachometer and transfe
r
case control module (TCCM) terminal 15 (if 4WD
model).
Engine Coolant Temperature (ECT) Sensor




















The ECT sensor is a thermistor. A temperature
changes the resistance value. And it changes voltage.
In other words it measures a temperature value. It is
installed on the coolant stream. Low coolan
t
temperature produces a high resistance.
The ECM supplies 5 volts signal to the ECT senso
r
through resisters in the ECM and measures the voltage.
The signal voltage will be high when the engine
temperature is cold, and it will be low when the engine
temperature is hot.

Characteris tic of ECT Sens or
10 100 1000 10000 100000-3010 50 90130Temperature (

)
Resistance (Ω)

6E-56 3.5L 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 oxygen senso
r
located in the exhaust system. The heated oxygen
sensor reports to the ECM how much oxygen is in the
exhaust gas. The ECM changes the air/fuel ratio to the
engine by controlling the amount of time that fuel
injector is "On".
The best mixture 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.

Acceleration Mode
The ECM provides extra fuel when it detects a rapid
increase in the throttle position and the air flow.

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.

Ignition dwell time.

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 80%
and the engine speed is below 800 RPM. If the throttle
position becomes less than 80%, the ECM again begins
to pulse the injectors "ON" and "OFF," allowing fuel into
the cylinders.

Deceleration Mode
The ECM reduces the amount of fuel injected when i
t
detects a decrease in the throttle position and the air
flow. When deceleration is very fast, the ECM may cu
t
off fuel completely for short periods.
Engine Speed/Vehicle Speed/Fuel Disable Mode
The ECM monitors engine speed. It turns off the fuel
injectors when the engine speed increase above 6400
RPM. The fuel injectors are turned back on when
engine speed decreases below 6150 RPM.

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 preven
t
engine flooding.

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). I
t
calculates the air/fuel ratio based on inputs from the TP,
ECT, and MAF 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.

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-79
TYPICAL SCAN DATA & DEFINITIONS (ENGINE DATA)
Use the typical values table only after the On-Board Diagnostic System check has been completed, no DTC(s) were noted, and you have determined that the On-Board
Diagnostic are functioning properly.
Tech2 values from a properly running engine may be used for comparison with the engine you are diagnosing.
Condition : Vehicle stopping, engine running, air conditioning off & after warm-up (Coolant temperature approximately 80
C)

Tech 2
Parameter
Units Idle 2000rpm Definitions
1 Ignition Voltage V 10.0  14.5 10.0  14.5 This displays the system voltage measured by the ECM at ignition feed.
2 Engine Speed rpm 710  860 1950  2050 The actual engine speed is measured by ECM from the CKP sensor 58X signal.
3 Desired Idle
Speed rpm 750  770 750  770 The desired engine idle speed that the ECM commanding.
The ECM compensates for various engine loads.
4 Engine Coolant
Temperature
C or
F 80  90 (

) 80  90 (

) The ECT is measured by ECM from ECT sensor output voltage.
When the engine is normally warm upped, this data displays approximately 80 °C or
more.
5 Start Up ECT
(Engine Coolant
Temperature)
C or
F Depends on ECT
at start-up
Depends on ECT
at start-up
Start-up ECT is measured by ECM from ECT sensor output voltage when engine is
started.
6 Intake Air
Temperature

C or
F Depends on
ambient temp.
Depends on
ambient temp.
The IAT is measured by ECM from IAT sensor output voltage.
This data is changing by intake air temperature.
7 Throttle Position % 0 4  6 Throttle position operating angle is measured by the ECM from throttle position
output voltage.
This should display 0% at idle and 99  100% at full throttle.
8 Throttle Position
Sensor V 0.4  0.7 0.6  0.8 The TPS output voltage is displayed.
This data is changing by accelerator operating angle.
9 Mass Air Flow g/s 5.0  8.0 13.0  16.0 This displays intake air amount.
The mass air flow is measured by ECM from the MAF sensor output voltage.
10 Air Fuel Ratio 14.7:1 14.7:1 This displays the ECM commanded value.
In closed loop, this should normally be displayed around 14.2:1  14.7:1.
11 Idle Air Control Steps 10  20 20  30 This displays the ECM commanded position of the idle air control valve pintle.
A larger number means that more air is being commanded through the idle air
passage.
12 EGR Valve V 0.00 0.00  0.10 The EGR position sensor output voltage is displayed.
This data is changing by EGR valve solenoid operating position.
13 Desired EGR
Opening V 0.00 0.05  1.10 The ECM commanded EGR position sensor voltage is displayed.
According to the current position, ECM changes EGR valve solenoid operating
position to meet the desired position.
14 EGR Valve On
Duty % 0 32 – 38 This displays the duty signal from the ECM to control the EGR valve.
15 Engine Load % 2  7 8  15 This displays is calculated by the ECM form engine speed and MAF sensor reading.
Engine load should increase with an increase in engine speed or air flow amount.
16 B1 Fuel System
Status Open Loop/ Close
Loop Close Loop Close Loop
17 B2 Fuel System
Status Open Loop/ Close
Loop Close Loop Close Loop
When the engine is first started the system is in "Open Loop" operation.
In "Open Loop", the ECM ignores the signal from the oxygen sensors.
When various conditions (ECT, time from start, engine speed & oxygen sensor
output) are met, the system enters "Closed Loop" operation.
In "Closed Loop", the ECM calculates the air fuel ratio based on the signal from the
oxygen sensors.
18 Fuel Trim
Learned (Bank 1) Yes/No Yes Yes
19 Fuel Trim
Learned (Bank 2) Yes/No Yes Yes
When conditions are appropriate for enabling long term fuel trim corrections, fuel trim
learn will display "Yes".
This indicates that the long term fuel trim is responding to the short term fuel trim.
If the fuel trim lean displays "No", then long term fuel trim will not respond to changes
in short term fuel trim.
20 Injection Pulse
Bank 1 ms 2.0  4.0 2.0  4.0
21 Injection Pulse
Bank 2 ms 2.0  4.0 2.0  4.0
This displays the amount of time the ECM is commanding each injector On during
each engine cycle.
A longer injector pulse width will cause more fuel to be delivered. Injector pulse width
should increase with increased engine load.
22 Spark Advance °CA 10  15 35  42 This displays the amount of spark advance being commanded by the ECM.

6E-82 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Tech 2
Parameter
Units Idle 2000rpm Definitions
19 B1 Short Term
Fuel Trim (Bank
1)
% -10
20 -10
20
20 B2 Short Term
Fuel Trim (Bank
2)
% -10
20 -10
20
The short term fuel trim to a bank represents a short term correction to the bank fuel
delivery by the ECM in response to the amount of time the bank fuel control oxygen
sensor voltage spends above or below the 450mV threshold.
If the oxygen sensor voltage has mainly remained less than 450mV, indicating a lean
air/fuel, short term fuel trim will increase into the positive range above 0% and the
ECM will pass fuel.
If the oxygen sensor voltage stays mainly above the threshold, short term fuel trim
will decrease below 0% into the negative range while the ECM reduces fuel delivery
to compensate for the indicated rich condition.
Under certain conditions such as extended idle and high ambient temperatures,
canister purge may cause short term fuel trim to read in the negative range during
normal operation.
Excessive short term fuel trim values may indicate an rich or lean condition.
21 Fuel Trim Cell 49
52 13
17 This displays dependent on engine speed and MAF sensor reading.
A plot of engine speed versus MAF amount is divided into the cells.
Fuel trim cell indicates which cell is currently active.
22 Fuel Trim
Learned (Bank 1) Yes/No Yes Yes
23 Fuel Trim
Learned (Bank 2) Yes/No Yes Yes
When conditions are appropriate for enabling long term fuel trim corrections, fuel trim
learn will display "Yes".
This indicates that the long term fuel trim is responding to the short term fuel trim.
If the fuel trim lean displays "No", then long term fuel trim will not respond to changes
in short term fuel trim.
24 B1S1 Status
(Bank 1 Sensor 1)
Rich / Lean Rich / Lean Rich / Lean
25 B2S1 Status
(Bank 2 Sensor 1)
Rich / Lean Rich / Lean Rich / Lean
This displays dependent on the exhaust oxygen sensor output voltage.
Should fluctuate constantly "Rich" and "Lean" in closed loop.

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E -89

After recording the snapshot in Tech2, transfer the data
from Tech2 to PC by the below procedures.
1.
Start TIS2000.
2.
Select [Snapshot Upload] on the TIS2000 start
screen.
3.
Select [Upload from trouble diagnosis tool (transfe
r
from diagnosis tester)] or click the corresponding
icon of the tool bar.
4.
Select Tech2, and transfer the recorded snapshot
information.
5.
Select the transferred snapshot.
6.
After ending transfer of the snapshot, data
parameter list is displayed on the screen. 3. Snapshot data is displayed with TIS2000
[Snapshot Upload] function.
Snapshot is stored in the PC hard disk or floppy disk,
and can be displayed any time.
Stored snapshot can be displayed by the below
procedures.
1.
Start TIS2000.
2.
Select [Snapshot Upload] on the TIS2000 start
screen.
3.
Select [Open the existing files] or click the
corresponding icon of the tool bar.
4.
Select the transferred snapshot.
5.
Open the snapshot, to display the data paramete
r
list on the screen.



Graph display Values and graphs (Max. 3 graphs):




1.
Click the icon for graph display. [Graph Parameter]
window opens.
2.
Click the first graph icon of the window upper part,
and select one parameter from the list of the
window lower part. Selected parameter is
displayed nest to the graph icon. Graph division
can be selected in the field on the parameter right
side.
3.
Repeat the same procedures with the 2nd and 3rd
icons.
4.
After selecting all parameters to be displayed
(Max. 3 parameters), click [OK] button.
5.
Parameter selected is displayed in graph form on
the right of the data parameter on the screen.

6.
Graph display can be moved with the navigation
icon.
7.
For displaying another parameter by graph, click
the parameter of the list, drug the mouse to the
display screen while pressing the mouse button
and release the mouse button. New parameter is
displayed at the position of the previous
parameter. For displaying the graph display screen
in full size, move the cursor upward on the screen.
When the cursor is changed to the magnifying
glass form, click the screen. Graph screen is
displayed on the whole screen.

6E-92 3.5L ENGINE DRIVEABILITY AND EMISSIONS

2.Demand of Data
1.
Connect Tech-2 to the vehicle. When activated b
y
turning on the power of Tech-2, push the "Enter"
switch.
2.
Turn on the ignition switch (without starting the
engine)
3.
In the main menu of Tech 2, push "F1: Service
Programming System (SPS)".
4.
Push "F0: Request Info" of Tech-2.

5.
Where vehicle data has been already saved in
Tech-2, the existing data come on display. In this
instance, as Tech-2 starts asking whether to keep
the data or to continue obtaining anew data from
the control unit, choose either of them.





6.
If you select “continue”, you have to select “Model
Year”, “Vehicle Type”.
7.
After that. then push button and turn Ignition switch
tuned on, off, on following Tech-2 display. Tech-2
will read information from controller after this
procedure.
8.
During obtaining information, Tech-2 is receiving
information from the control unit ECM and TCM
(A/T only) at the same time. With VIN not being
programmed into the new control unit at the time
of shipment, "obtaining information" is not
complete (because the vehicle model, engine
model and model year are specified from VIN). Fo
r
the procedure get additional information on
vehicles, instruction will be provided in dialog form,
when TIS2000 is in operation.
9.
Following instructions by Tech-2, push the "Exit"
switch of Tech-2, turn off the ignition of the vehicle
and turn off the power of Tech-2, thereby removing
from the vehicle.


3.Data Exchange
1.
Connect Tech-2 to P/C, turn on the power and
click the "Next" button of P/C.
2. Check VIN of the vehicle and choose "Next".
3. Select “System Type” for required control unit.


Engine (Programming for ECM or PCM)


Transmission (Programming for TCM)
4.
When a lack of data is asked from among the
following menu, enter accordingly.

Select following Menu


Model Year


Model


Engine type


Transmission type


Destination code (vehicles for general export)*1


Immobilizer
Etc.
* 1: How to read the destination code
"Destination code can be read from service ID Plate
affixed on vehicles, while on service ID plate the
destination code is described at the right-hand edge o
f
Body Type line. In the figure, the destination code can
be read as "RR3" (Australia).