2002 ISUZU AXIOM Fuel injection pulse

0A±13
GENERAL INFORMATION
N Ð Newtons
NA Ð Natural Aspirated
NC Ð Normally Closed
N´M Ð Newton Meters
NO Ð Normally Open
NOX Ð Nitrogen, Oxides of
OBD Ð On-Board Diagnostic
OD Ð Outside Diameter
O/D Ð Over Drive
OHC Ð Overhead Camshaft
OL Ð Open Loop
O2 Ð Oxygen
O2S Ð Oxygen Sensor
PAIR Ð Pulsed Secondary Air Injection System
P/B Ð Power Brakes
PCM Ð Powertrain Control Module
PCV Ð Positive Crankcase Ventilation
PRESS Ð Pressure
PROM Ð Programmable Read Only Memory
PNP Ð Park/Neutral Position
P/S Ð Power Steering
PSI Ð Pounds per Square Inch
PSP Ð Power Steering Pressure
Pt. Ð Pint
Pri Ð Primary
PWM Ð Pulse Width Modulate
Qt. Ð Quart
REF Ð Reference
RF Ð Right Front
RFI Ð Radio Frequency Interference
RH Ð Right Hand
RPM Ð Revolutions Per Minute
RPM Sensor Ð Engine Speed Sensor
RPO Ð Regular Production Option
RR Ð Right Rear
RS Ð Right Side
RTV Ð Room Temperature Vulcanizing
RWAL Ð Rear Wheel Antilock Brake
RWD Ð Rear Wheel Drive
SAE Ð Society of Automotive Engineers
Sec Ð Secondary
SFI Ð Sequential Multiport Fuel Injection
SI Ð System International
SIR Ð Supplemental Inflatable Restraint System
SOHC Ð Single Overhead Camshaft
Sol Ð Solenoid
SPEC Ð Specification
Speedo Ð Speedometer
SRS Ð Supplemental Restraint System
ST Ð Start / Scan Tool
Sw Ð Switch
SWB Ð Short Wheel Base
SYN Ð Synchronize
Tach Ð Tachometer
TB Ð Throttle Body
TBI Ð Throttle Body Fuel Injection
TCC Ð Torque Converter Clutch
TCM Ð Transmission Control Module
TDC Ð Top Dead Center
Term Ð Terminal
TEMP Ð Temperature
TODÐ Torque On Demand
TP Ð Throttle Position
TRANS Ð Transmission/Transaxle
TURBO Ð TurbochargerTVRS Ð Television & Radio Suppression
TVV Ð Thermal Vacuum Valve
TWC Ð Three Way Catalytic Converter
3 A/T Ð Three Speed Automatic Transmission/Transaxle
2WD Ð Two Wheel Drive
4 x 2 Ð Two Wheel Drive
U±joint Ð Universal Joint
V Ð Volt(s)
VAC Ð Vacuum
VIN Ð Vehicle Identification Number
VRRRE Ð Vehicle Refrigerant Recovery and Recycling
Equipment
V±ref Ð ECM Reference Voltage
VSS Ð Vehicle Speed Sensor
VSV Ð Vacuum Switch Valve
V±6 Ð Six Cylinder ªVº Engine
V±8 Ð Eight Cylinder ºVº Engine
W Ð Watt(s)
w/ Ð With
w/b Ð Wheel Base
w/o Ð Without
WOT Ð Wide Open Throttle
Service Parts Identification Plate
The Vehicle Information Plate (Service Parts ID plate) is
provided on all vehicle models.
It is located on the center dash wall inside the engine
compartment. The plate lists the VIN (Vehicle
Identification Number), paint information and all
production options and special equipment on the vehicle
when it was shipped from the factory.
905R200002

6C±3 ENGINE FUEL (6VE1 3.5L)
When working on the fuel system, there are several
things to keep in mind:

Any time the fuel system is being worked on,
disconnect the battery ground cable except for those
tests where battery voltage is required.

Always keep a dry chemical (Class B) fire
extinguisher near the work area.

Replace all pipes with the same pipe and fittings that
were removed.

Clean and inspect ªOº rings. Replace if required.

Always relieve the line pressure before servicing any
fuel system components.

Do not attempt repairs on the fuel system until you
have read the instructions and checked the pictures
relating to that repair.

Adhere to all Notices and Cautions.
All gasoline engines are designed to use only unleaded
gasoline. Unleaded gasoline must be used for proper
emission control system operation.
Its use will also minimize spark plug fouling and extend
engine oil life. Using leaded gasoline can damage the
emission control system and could result in loss of
emission warranty coverage.
The vapor pressure sensor and vent solenoid valve for
vapor pressure sensor are used to detect abnormalities in
the evaporative emission control system.
The PCM decides whether there is an abnormality in the
evaporative emission control system based on vapor
pressure sensor signal.Fuel Metering
The Powertrain Control Module (PCM) 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 Manifold Absolute Pressure (MAP) sensor measures
the changes in the intake manifold pressure which result
from engine load and speed changes, which the MAP
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 PCM.
With receipt of the signals sent from the MAP sensor,
Intake Air Temperature sensor and others, the PCM
determines an appropriate fuel injection pulse width
feeding such information to the fuel injector valves to
affect an appropriate air/fuel ratio.
The Multiport Fuel Injection system utilizes an injection
system where the injectors turn on at every crankshaft
revolution. The PCM controls the injector on time so that
the correct amount of fuel is metered depending on
driving conditions.
Two interchangeable ªOº rings are used on the injector
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 weather
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 ªDriveability and Emissionº for more
information and diagnosis.

6E±578
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
General Description (Fuel Metering)
Acceleration Mode
The PCM 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 PCM 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 PCM then de-energizes the fuel
injectors. The PCM 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 PCM again begins to pulse the
injectors ªONº and ªOFF,º allowing fuel into the cylinders.
Deceleration Mode
The PCM 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 PCM may cut off fuel
completely for short periods.
Engine Speed/Vehicle Speed/Fuel Disable
Mode
The PCM monitors engine speed. It turns off the fuel
injectors when the engine speed increases 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 ªOFF.º This prevents engine run-on. In addition, the
PCM suspends fuel delivery if no reference pulses are
detected (engine not running) to prevent engine flooding.
Fuel Injector
The sequential multiport fuel injection (SFI) fuel injector is
a solenoid-operated device controlled by the PCM. The
PCM energizes the solenoid, which opens a valve to allow
fuel delivery.
The fuel is injected under pressure in a conical spray
pattern at the opening of the intake valve. Excess fuel not
used by the injectors passes through the fuel pressure
regulator before being returned to the fuel tank.
A fuel injector which is stuck partly open will cause a loss
of fuel pressure after engine shut down, causing long
crank times.
014RY00009
Fuel Metering System Components
The fuel metering system is made up of the following
parts:

The fuel injectors.

The throttle body.

The fuel rail.

The fuel pressure regulator.

The PCM.

The crankshaft position (CKP) sensor.

The ION sensing module.

The fuel pump.

The fuel pump relay.
Basic System Operation
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. Refer to
Section 6C for
further information on the fuel tank, line filter, and fuel
pipes.
Fuel Metering System Purpose
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 near each intake valve.
The main control sensor is the heated oxygen sensor
(HO2S) located in the exhaust system. The HO2S tells
the PCM how much oxygen is in the exhaust gas. The
PCM changes the air/fuel ratio to the engine by controlling
the amount of time that fuel injector is ªON.º 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 ªclosed loopº system.

6E±581
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Vehicle speed (vehicle speed sensor).

PCM and ignition system supply voltage.

The crankshaft position (CKP) sensor sends the PCM
a 58X signal related to the exact position of the
crankshaft.
TS22909Based on these sensor signals and engine load
information, the PCM sends 5V to each ignition coil.
060RY00116This module has the function to energize and de-energize
the primary ignition coil in response to signals from the
PCM. The Throttle PCM controls ignition timing and dwell
time.
Continuity and out-or-range value check:
This diagnosis detects open circuit or short-circuiting in
the Electronic Spark Timing (EST) line by monitoring EST
signals. A failure determination is made when the signal
voltage remains higher or lower than the threshold for
corresponding fault code beyond a predetermined time
period.
Diagnosis enabling conditions are as follows:

RPM is higher than the specified threshold.
EST line is enabled.
060RY00029
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 ignition coil assembly (ºcoil-at-plugº) 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. When the PCM shuts off the 5-volt signal to the
ION sensing 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
Powertrain Control Module (PCM)
The PCM is responsible for maintaining proper spark and
fuel injection timing for all driving conditions. To provide
optimum 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) .

ENTERTAINMENT8C±17
MID Self-Diagnosis
StepActionValue(s)Ye sNo
11. Simultaneously press and hold the RESET key and
the CLOCK key (on the display panel).
2. Turn the ignition switch to the ON position.
Does DIAG appear on the display screen?
ÐGo to Step 2
Check power
supply and
components
connections.
Start
self-diagnosis
again.
2Press and release the CLOCK key (1 time only).
Does DIAG MID appear on the display?
ÐGo to Step 3Ð
3Press and release the CLOCK key (1 time only) to
begin GPS communications diagnosis.
Does GPS OK appear on the display?
ÐGo to Step 5
On ERROR1,
Go to
Step 4
4Repair open circuit between MID and GPS receiver
(I-13±2 ~ I-16±5).
Is the action complete?
ÐGo to Step 1Ð
5Press and release the CLOCK key (1 time only) to
begin fuel injection pulse diagnosis.
Does F-INJ OK appear on the display?
ÐGo to Step 7
On ERROR2,
Go to
Step 6
6Repair open fuel injection pulse circuit (I-13±5 ~
E35±8).
Is the action complete?
ÐGo to Step 1Ð
7Press and release the CLOCK key (1 time only) to
begin fuel remainder pulse diagnosis.
Does F-SENS OK appear on the display?
ÐGo to Step 9
On ERROR3,
Go to
Step 9
8Repair open fuel remainder pulse circuit (I-13±6 ~
E35±48).
Is the action complete?
ÐGo to Step 1Ð
9Press and release the CLOCK key (1 time only) to
begin gyro-sensor diagnosis.
Does GYRO OK appear on the display?
ÐGo to Step 11
On ERROR4,
Go to
Step 10
10Replace the MID control unit.
Is the action complete?
ÐGo to Step 1Ð
111. Press and release the CLOCK key (1 time only) to
begin vehicle speed sensor diagnosis.
2. Drive vehicle.
Does SPEED OK appear on the display?
ÐGo to Step 13
On ERROR5,
Go to
Step 12
12Repair open vehicle speed sensor circuit (I-13±15 ~
E43±3).
Is the action complete?
ÐGo to Step 1Ð
13Press and release ON/OFF key to return to start of
diagnosis screen.
Is the action complete?
ÐGo to Step 1Go to Step 14
14Press and release the SERVICE key.
Is the action complete?
ÐGo to Step 2Ð