fuel pressure ISUZU AXIOM 2002 Service Owner's Guide

6E±16
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
PCM Pinout Table, 80-Way Blue Connector ± Row ªF41 ~ 60º
060RY00046
PINPIN FunctionWire ColorIGN ONENG RUNRefer To
F41Throttle Position(TP) 1
Sensor GroundGRN0.0V0.0VGeneral Description and
Operation, TPS
F42Fuel Pump RelayPNK/WHT0.0VB+On Vehicle Service, Fuel
Pump Relay
F43Adaptor CaseVIO/RED0.0V0.0V4L30E T/Mission
F44Bank 1 HO2S 2 Heater
GroundORN/WHT0.0V0.0VGeneral Description and
Operation, Catalyst Monitor
HO2S 2
F45A/C RequestGRN/BLK0.0V0.0VChassis Electrical
F46Stop Lamp SwitchBRN/RED0.0V0.0VChassis Electrical
F47Adaptor CaseVIO/WHTB+B+4L30E T/Mission
F48Throttle Valve DC Motor(±:
REV)BLUDuty CycleDuty CycleGeneral Description and
Operation, ETC
F49Not UsedÐÐÐÐ
F50Bank 2 HO2S 2 GroundORN0.0V0.0VÐ
F51Not UsedÐÐÐÐ
F52Bank 1 HO2S 2 GroundRED0.0V0.0VÐ
F53ECT GroundYEL/BLK0.0V0.0VGeneral Description and
Operation, ECT Sensor
F54Vapor Pressure (Fuel Tank
Pressure) Sensor GroundGRN0.0V0.0VGeneral Description and
Operation, VP Sensor
F55Not UsedÐÐÐÐ
F56Injector Cylinder #5GRN/BLKB+B+General Description and
Operation, Fuel Injector
F57Ignition FeedRED/WHTB+B+Chassis Electrical
F58Class 2 DataORN/BLK0.0V0.0VGeneral Description
F59Not UsedÐÐÐÐ
F60Not UsedÐÐÐÐ

6E±21
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
PCM Pinout Table, 80-Way Red Connector ± Row ªS21 ~ 40º
060RY00049
PINPIN FunctionWire ColorIGN ONENG RUNRefer To
S21AudioYEL/GRNÐÐChassis Electrical
S22Transmission Output
Speed SensorBLU/YEL0.0V0.0V4L30E T/Mission
S23PCM GroundBLK0.0V0.0VChassis Electrical
S24Bank 1 HO2S 2 GroundRED0.0V0.0VÐ
S25Not UsedÐÐÐÐ
S26EGR Control HighBLU/REDB+B+General Description and
Operation, EGR Control
S27VSS InputBLK/YEL0.0V0.1V (at rest)Chassis Electrical
S28Injector Cylinder #6GRN/YELB+B+General Description and
Operation, Fuel Injector
S29Winter SwitchVIO/GRNB+B+4L30E T/Mission
S30Auto Cruise Main SwitchWHT/RED0.0V0.0VChassis Electrical
S31Shift SolenoidGRN0.0V0.0V4L30E T/Mission
S32Ignition FeedRED/GRNB+B+Chassis Electrical
S33TCC SolenoidBRN/WHT0.0V0.0VT/Mission
S34Not UsedÐÐÐÐ
S35ION Sensing ModuleRED/GRN1.555V1.555VGeneral Description and
Operation, ION Sensing
Module
S365Volt Reference (AP
Sensor 1)BLK5.0V5.0VAP Sensor
S375Volt Reference (Vapor
Pressure {Fuel Tank
Pressure} Sensor/MAP
Sensor/EGR Position
Sensor)GRY/RED5.0V5.0V(Fuel Tank Pressure
Sensor/MAP Sensor/EGR
Position Sensor) Sensor
S385Volt Reference (TP
Sensor 1)RED5.0V5.0VTP Sensor

6E±23
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
PCM Pinout Table, 80-Way Red Connector ± Row ªS41 ~ 60º
060RY00050
PINPIN FunctionWire ColorIGN ONENG RUNRefer To
S41AP Sensor 3 Sensor
GroundORN/BLU0.0V0.0VOn-Vehicle Service
S42Bank 2 HO2S 1 Heater
GroundWHT/RED0.0V0.0VGeneral Description and
Operation, Catalyst Monitor
HO2S
S43Solenoid Power SupplyGRY/WHTB+B+4L30E T/Mission
S44Rr Def. RelayRED/WHTÐÐÐ
S45Starter RelayBLK/BLUÐÐÐ
S46Fuel GaugeYEL/REDB+B+Chassis Electrical
S47Water Temp. GaugeWHT/BLKB+B+4L30E T/Mission
S48Fuel GaugeYEL/REDB+B+General Description and
Chassis Electrical
S49DLCRED/WHTB+B+General Description
S50Fuel Sender UnitORN/GRN0.0V0.0VÐ
S51TCC SolenoidBRN/BLU0.0V0.0VT/Mission
S52Vapor Pressure (Fuel Tank
Pressure) Sensor SignalGRY0.2±4.8V0.2±4.8VGeneral Description and
Operation, VP Sensor
S53Power SwitchVIO/REDB+B+4L30E T/Mission
S54Bank 2 HO2S 1 LowBLU0.0V0.1VGeneral Description and
Operation, Catalyst Monitor
HO2S
S55Transmission Output
Speed SensorBLU/GRN0.0V0.0V4L30E T/Mission
S56Not UsedÐÐÐÐ
S57Not UsedÐÐÐÐ
S58Bank 1 HO2S 1 HighORN/BLU0.3V0.1±0.9VGeneral Description and
Operation, Catalyst Monitor
HO2S

6E±28
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Engine Component Locator Table
Number
NameLocation
1Linear Exhaust Gas Recirculation (EGR) ValveRear right side of the engine
2Throttle Position (TP) SensorOn the throttle body
3Intake Air Temperature (IAT) SensorOn the intake air duct near the throttle body
4Check Engine (MIL) LightOn the instrument panel beneath the
tachometer
5Positive Crankcase Ventilation (PCV) ValveOn the left of the cylinder head cover
6Air CleanerLeft front of the engine bay
7Mass Air Flow (MAF) SensorAttached to the air filter box
8Fuel RailOn the Common Chamber
9Fuel Pressure RegulatorRear side of the engine
10ION Sensing moduleBolted to the top of the Common Chamber
11Common ChamberTop of the engine
12EVAP Duty Solenoid ValveBolted to the front of the coolant pipe
13Fuse/Relay BoxAlong the inside of the right fender
14Manifold Absolute Pressure (MAP) SensorBolted to the top of the Common Chamber
15Throttle BodyBetween the intake air duct and the Common
Chamber
16Engine Coolant Temperature SensorOn the coolant crossover pipe at the front of
the engine, near the throttle body
17Power Train Control Module (PCM)Along the inside of the left fender

6E±29
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Undercarriage Component Locator
014RW142
Undercarriage Component Locator Table
Number
NameLocation
1Fuel Pump Assembly and Vapor Pressure
(Fuel Tank Pressure) SensorInstalled in the top of the fuel tank
2Fuel Gauge UnitInstalled in the top of the fuel tank
3Evaporative (EVAP) CanisterOn the top of the bracket that is located behind
the cross member
4Vent Solenoid (EVAP Canister)On the top of the bracket that is located behind
the cross member
5Fuel FilterLocated along the inside of the right frame rail,
ahead of the fuel tank
6Vehicle Speed Sensor (VSS)Protrudes from the transmission housing, just
ahead of the propeller shaft
7Heated Oxygen Sensor (Bank 1, HO2S 1)Threaded into the exhaust pipe behind the
right-hand catalytic converter
8Heated Oxygen Sensor (Bank 1, HO2S 2)Threaded into the exhaust pipe ahead of the
right-hand catalytic converter
9Heated Oxygen Sensor (Bank 2, HO2S 1)Threaded into the exhaust pipe ahead of the
left-hand catalytic converter
10Heated Oxygen Sensor (Bank 2, HO2S 2)Threaded into the exhaust pipe behind the
left-hand catalytic converter

6E±34
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
dissatisfaction. The following list of non-vehicle faults
does not include every possible fault and may not apply
equally to all product lines.
Fuel Quality
Fuel quality is not a new issue for the automotive industry,
but its potential for turning on the MIL (ªCheck Engineº
lamp) with OBD II systems is new.
Fuel additives such as ªdry gasº and ªoctane enhancersº
may affect the performance of the fuel. If this results in an
incomplete combustion or a partial burn, it will show up as
a Misfire DTC P0300. The Reed Vapor Pressure of the
fuel can also create problems in the fuel system,
especially during the spring and fall months when severe
ambient temperature swings occur. A high Reed Vapor
Pressure could show up as a Fuel Trim DTC due to
excessive canister loading. High vapor pressures
generated in the fuel tank can also affect the Evaporative
Emission diagnostic as well.
Using fuel with the wrong octane rating for the vehicle
may cause driveability problems. Many of the major fuel
companies advertise that using ªpremiumº gasoline will
improve the performance of the vehicle. Most premium
fuels use alcohol to increase the octane rating of the fuel.
Although alcohol-enhanced fuels may raise the octane
rating, the fuel's ability to turn into vapor in cold
temperatures deteriorates. This may affect the starting
ability and cold driveability of the engine.
Low fuel levels can lead to fuel starvation, lean engine
operation, and eventually engine misfire.
Non-OEM Parts
All of the OBD II diagnostics have been calibrated to run
with OEM parts. Something as simple as a
high-performance exhaust system that affects exhaust
system back pressure could potentially interfere with the
operation of the EGR valve and thereby turn on the MIL
(ªCheck Engineº lamp). Small leaks in the exhaust
system near the post catalyst oxygen sensor can also
cause the MIL (ªCheck Engineº lamp) to turn on.
Aftermarket electronics, such as transceivers, stereos,
and anti-theft devices, may radiate EMI into the control
system if they are improperly installed. This may cause a
false sensor reading and turn on the MIL (ªCheck Engineº
lamp).
Environment
Temporary environmental conditions, such as localized
flooding, will have an effect on the vehicle ignition system.
If the ignition system is rain-soaked, it can temporarily
cause engine misfire and turn on the MIL (ªCheck Engineº
lamp).
Refueling
A new OBD II diagnostic was introduced in 1996 on some
vehicles. This diagnostic checks the integrity of the entire
evaporative emission system. If the vehicle is restarted
after refueling and the fuel cap is not secured correctly,
the on-board diagnostic system will sense this as a
system fault and turn on the MIL (ªCheck Engineº lamp)
with a DTC P0440.Vehicle Marshaling
The transportation of new vehicles from the assembly
plant to the dealership can involve as many as 60 key
cycles within 2 to 3 miles of driving. This type of operation
contributes to the fuel fouling of the spark plugs and will
turn on the MIL (ªCheck Engineº lamp) with a P0300
Misfire DTC.
Poor Vehicle Maintenance
The sensitivity of OBD II diagnostics will cause the MIL
(ªCheck Engineº lamp) to turn on if the vehicle is not
maintained properly. Restricted air filters, fuel filters, and
crankcase deposits due to lack of oil changes or improper
oil viscosity can trigger actual vehicle faults that were not
previously monitored prior to OBD II. Poor vehicle
maintenance can't be classified as a ªnon-vehicle faultº,
but with the sensitivity of OBD II diagnostics, vehicle
maintenance schedules must be more closely followed.
Related System Faults
Many of the OBD II system diagnostics will not run if the
PCM detects a fault on a related system or component.
One example would be that if the PCM detected a Misfire
fault, the diagnostics on the catalytic converter would be
suspended until Misfire fault was repaired. If the Misfire
fault was severe enough, the catalytic converter could be
damaged due to overheating and would never set a
Catalyst DTC until the Misfire fault was repaired and the
Catalyst diagnostic was allowed to run to completion. If
this happens, the customer may have to make two trips to
the dealership in order to repair the vehicle.
Emissions Control Information Label
The engine compartment ªVehicle Emissions Control
Information Labelº contains important emission
specifications and setting procedures. In the upper left
corner is exhaust emission information. This identifies
the emission standard (Federal, California, or Canada) of
the engine, the displacement of the engine in liters, the
class of the vehicle, and the type of fuel metering system.
There is also an illustrated emission components and
vacuum hose schematic.
This label is located in the engine compartment of every
vehicle. If the label has been removed it should be
replaced. It can be ordered from Isuzu Dealership.
Visual / Physical Engine Compartment
Inspection
Perform a careful visual and physical engine
compartment inspection when performing any diagnostic
procedure or diagnosing the cause of an emission test
failure. This can often lead to repairing a problem without
further steps. Use the following guidelines when
performing a visual/physical inspection:

Inspect all vacuum hoses for pinches, cuts,
disconnections, and proper routing.

Inspect hoses that are difficult to see behind other
components.

6E±35
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Inspect all wires in the engine compartment for proper
connections, burned or chafed spots, pinched wires,
contact with sharp edges or contact with hot exhaust
manifolds or pipes.
Basic Knowledge of Tools Required
NOTE: Lack of basic knowledge of this powertrain when
performing diagnostic procedures could result in an
incorrect diagnosis or damage to powertrain
components. Do not attempt to diagnose a powertrain
problem without this basic knowledge.
A basic understanding of hand tools is necessary to effec-
tively use this section of the Service Manual.
Serial Data Communications
Class 2 Serial Data Communications
Government regulations require that all vehicle
manufacturers establish a common communication
system. This vehicle utilizes the ªClass 2º communication
system. Each bit of information can have one of two
lengths: long or short. This allows vehicle wiring to be
reduced by transmitting and receiving multiple signals
over a single wire. The messages carried on Class 2 data
streams are also prioritized. If two messages attempt to
establish communications on the data line at the same
time, only the message with higher priority will continue.
The device with the lower priority message must wait.
The most significant result of this regulation is that it
provides Scan tool manufacturers with the capability to
access data from any make or model vehicle that is sold.
The data displayed on other Scan tools will appear the
same, with some exceptions. Some Scan tools will only
be able to display certain vehicle parameters as values
that are a coded representation of the true or actual value.
On this vehicle the Scan tool displays the actual values for
vehicle parameters. It will not be necessary to perform
any conversions from coded values to actual values.
On-Board Diagnostic (OBD II)
On-Board Diagnostic Tests
A diagnostic test is a series of steps, the result of which is
a pass or fail reported to the diagnostic executive. When
a diagnostic test reports a pass result, the diagnostic
executive records the following data:

The diagnostic test has been completed since the last
ignition cycle.

The diagnostic test has passed during the current
ignition cycle.

The fault identified by the diagnostic test is not
currently active.
When a diagnostic test reports a fail result, the diagnostic
executive records the following data:

The diagnostic test has been completed since the last
ignition cycle.

The fault identified by the diagnostic test is currently
active.

The fault has been active during this ignition cycle.

The operating conditions at the time of the failure.Remember, a fuel trim DTC may be triggered by a list of
vehicle faults. Make use of all information available (other
DTCs stored, rich or lean condition, etc.) when
diagnosing a fuel trim fault.
Comprehensive Component Monitor
Diagnostic Operation
Comprehensive component monitoring diagnostics are
required to monitor emissions-related input and output
powertrain components. The
CARB OBD II
Comprehensive Component Monitoring List Of
Components Intended To illuminate MIL
is a list of
components, features or functions that could fall under
this requirement.
Input Components:
Input components are monitored for circuit continuity and
out-of-range values. This includes rationality checking.
Rationality checking refers to indicating a fault when the
signal from a sensor does not seem reasonable, i.e.
Throttle Position (TP) sensor that indicates high throttle
position at low engine loads or MAP voltage. Input
components may include, but are not limited to the
following sensors:

Vehicle Speed Sensor (VSS)

Crankshaft Position (CKP) sensor

Throttle Position (TP) sensor

Engine Coolant Temperature (ECT) sensor

Manifold Absolute Pressure (MAP) sensor

Mass Air Flow (MAF) sensor
In addition to the circuit continuity and rationality check,
the ECT sensor is monitored for its ability to achieve a
steady state temperature to enable closed loop fuel
control.
Output Components:
Output components are diagnosed for proper response to
control module commands. Components where
functional monitoring is not feasible will be monitored for
circuit continuity and out-of-range values if applicable.
Output components to be monitored include, but are not
limited to, the following circuits:

Control module controlled EVAP Canister Purge
Valve

Electronic Transmission controls

A/C relays

VSS output

MIL control

Cruise control inhibit
Refer to PCM and Sensors in General Descriptions.
Passive and Active Diagnostic Tests
A passive test is a diagnostic test which simply monitors a
vehicle system or component. Conversely, an active test,
actually takes some sort of action when performing
diagnostic functions, often in response to a failed passive
test. For example, the EGR diagnostic active test will
force the EGR valve open during closed throttle decel
and/or force the EGR valve closed during a steady state.
Either action should result in a change in manifold
pressure.

6E±36
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Intrusive Diagnostic Tests
This is any on-board test run by the Diagnostic
Management System which may have an effect on
vehicle performance or emission levels.
Warm-Up Cycle
A warm-up cycle means that engine at temperature must
reach a minimum of 70
C (160
F)
and rise at least 22
C
(40
F) over the course of a trip.
Freeze Frame
Freeze Frame is an element of the Diagnostic
Management System which stores various vehicle
information at the moment an emissions-related fault is
stored in memory and when the MIL is commanded on.
These data can help to identify the cause of a fault. Refer
to
Storing And Erasing Freeze Frame Data in this section
for more detailed information.
Failure Records
Failure Records data is an enhancement of the OBD II
Freeze Frame feature. Failure Records store the same
vehicle information as does Freeze Frame, but it will store
that information for any fault which is stored in on-board
memory, while Freeze Frame stores information only for
emission-related faults that command the MIL on.
System Status and Drive Cycle for
Satisfying Federal Inspection/Maintenance
(I/M 240) Regulations
I/M Ready Status means a signal or flag for each
emission system test that had been set in the PCM. I/M
Ready Status indicates that the vehicle on-board
emissions diagnostics have been run. I/M Ready Status
is not concerned whether the emission system passed or
failed the test, only that on-board diagnosis is complete.
Not all vehicles use all possible I/M flags.
Common OBD II Terms
Diagnostic
When used as a noun, the word diagnostic refers to any
on-board test run by the vehicle's Diagnostic
Management System. A diagnostic is simply a test run on
a system or component to determine if the system or
component is operating according to specification. There
are many diagnostics, shown in the following list:

Misfire

Oxygen sensors

Oxygen sensor heaters

EGR

Catalyst monitoring
Enable Criteria
The term ªenable criteriaº is engineering language for the
conditions necessary for a given diagnostic test to run.
Each diagnostic has a specific list of conditions which
must be met before the diagnostic will run. ªEnable
criteriaº is another way of saying ªconditions requiredº.The enable criteria for each diagnostic is listed on the first
page of the DTC description in Section 6E under the
heading ªConditions for Setting the DTCº. Enable criteria
varies with each diagnostic, and typically includes, but is
not limited to the following items:

engine speed

vehicle speed

ECT

MAF/MAP

barometric pressure

IAT

TP

high canister purge

fuel trim

TCC enabled

A/C on
Trip
Technically, a trip is a key on-run-key off cycle in which all
the enable criteria for a given diagnostic are met, allowing
the diagnostic to run. Unfortunately, this concept is not
quite that simple. A trip is official when all the enable
criteria for a given diagnostic are met. But because the
enable criteria vary from one diagnostic to another, the
definition of trip varies as well. Some diagnostics are run
when the vehicle is at operating temperature, some when
the vehicle first starts up; some require that the vehicle be
cruising at a steady highway speed, some run only when
the vehicle is idle; some diagnostics function with the
TCC disabled. Some run only immediately following a
cold engine start-up.
A trip then, is defined as a key on-run-key off cycle in
which the vehicle was operated in such a way as to satisfy
the enabling criteria for a given diagnostic, and this
diagnostic will consider this cycle to be one trip. However,
another diagnostic with a different set of enable criteria
(which were not met) during this driving event, would not
consider it a trip. No trip will occur for that particular
diagnostic until the vehicle is driven in such a way as to
meet all the enable criteria.
The Diagnostic Executive
The Diagnostic Executive is a unique segment of
software which is designed to coordinate and prioritize
the diagnostic procedures as well as define the protocol
for recording and displaying their results. The main
responsibilities of the Diagnostic Executive are listed as
the following:

Commanding the MIL (ªCheck Engineº lamp) on and
off

DTC logging and clearing

Freeze Frame data for the first emission related DTC
recorded

Non-emission related Service Lamp

Operating conditions Failure Records buffer, (the
number of records will vary)

Current status information on each diagnostic

System Status (I/M ready)

6E±68
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Electronic Ignition System Diagnosis
If the engine cranks but will not run or immediately stalls,
the Engine Cranks But Will Not Start chart must be used
to determine if the failure is in the ignition system or the
fuel system. If DTC P0300 through P0306, P0341, or
P0336 is set, the appropriate diagnostic trouble code
chart must be used for diagnosis.
If a misfire is being experienced with no DTC set, refer to
the
Symptoms section for diagnosis.
EVAP Canister Purge Solenoid and
EVAP Vent Solenoid Valve
A continuous purge condition with no purge commanded
by the PCM will set a DTC P1441. Refer to the DTC charts
for further information.
Visual Check of The Evaporative
Emission Canister

If the canister is cracked or damaged, replace the
canister.

If fuel is leaking from the canister, replace the canister
and check hoses and hose routing.
Fuel Metering System Check
Some failures of the fuel metering system will result in an
ªEngine Cranks But Will Not Runº symptom. If this
condition exists, refer to the
Cranks But Will Not Run
chart. This chart will determine if the problem is caused
by the ignition system, the PCM, 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. 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 PCM 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
Tech 2. Ideal long term fuel trim values are around 0%;
for a lean HO2S signal, the PCM will add fuel, resulting in
a fuel trim value above 0%. Some variations in fuel trim
values are normal because all engines are not exactly the
same. If the evaporative emission canister purge is ªONº,
the fuel trim may be as low as ±38%. If the fuel trim values
are greater than +23%, refer to
DTC P0131, DTC P0151,
DTC P0171, and DTC 1171
for items which can cause a
lean HO2S signal.
Fuel System Pressure Test
A fuel system pressure test is part of several of the
diagnostic charts and symptom checks. To perform this
test, refer to
Fuel Systems Diagnosis.
Fuel Injector Coil Test Procedure and
Fuel Injector Balance Test Procedure
T32003
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart:
2. Relieve the fuel pressure by connecting the J
34730-1 Fuel Pressure Gauge 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 ªOFFº, 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:
Resistance (Ohms)
Voltage Specification at
10
C-35
C (50
F-95
F)
11.8 ± 12.65.7 ± 6.6

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.

6E±69
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

An erratic voltage reading (large fluctuations in
voltage that do not stabilize) indicates an
intermittent connection within the fuel injector.
5. Injector Specifications:
Highest Acceptable
Voltage Reading
Above/Below 35
C/10
C
(95
F/50
F)
Acceptable Subtracted
Value
9.5 Volts0.6 Volts
7. The Fuel Injector Balance Test portion of this chart
(Step 7 through Step 11) checks the mechanical
(fuel delivery) portion of the fuel injector. An engine
cool-down period of 10 minutes is necessary in
order to avoid irregular fuel pressure readings due
to ªHot Soakº fuel boiling.
Injector Coil Test Procedure (Steps 1-6) and Injector Balance Test Procedure
(Steps 7-11)
R262001
CYLINDER123456
1st Reading (1)296 kPa
(43 psi)296 kPa
(43 psi)296 kPa
(43 psi)296 kPa
(43 psi)296 kPa
(43 psi)296 kPa
(43 psi)
2nd Reading (2)131 kPa
(19 psi)117 kPa
(17 psi)124 kPa
(18 psi)145 kPa
(21 psi)131 kPa
(19 psi)130 kPa
(19 psi)
Amount of Drop (1st
Reading±2nd Reading)165 kPa
(24 psi)179 kPa
(26 psi)172 kPa
(25 psi)151 kPa
(22 psi)165 kPa
(24 psi)166 kPa
(24 psi)
Av.drop = 166 kPa/24 psi +
10 kPa/1.5 psi
= 156 ± 176 kPa or
22.5 ± 25.5 psiOKFaulty, Rich
(Too Much
Fuel Drop)OKFaulty, Lean
(Too Little
Fuel Drop)OKOK
NOTE: These figures are examples only.