oil temperature ISUZU TF SERIES 2004 Owner's Manual

6E-2 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Visual/Physical Engine Compartment
Inspection ...................................................... 6E-74
Basic Knowledge of Tools Required............... 6E-71
Serial Data Communications .......................... 6E-71
On-Board Diagnostic (OBD) ........................... 6E-71
Comprehensive Component Monitor
Diagnostic Operation ..................................... 6E-71
The Diagnostic Executive ............................... 6E-72
Verifying Vehicle Repair ................................. 6E-73
Reading Flash Diagnostic Trouble Codes ...... 6E-73
Reading Diagnostic Trouble Codes Using
a Tech 2......................................................... 6E-73
On-Board Diagnosis (Self-Diagnosis)............. 6E-74
Diagnosis with Tech 2 .................................... 6E-75
TYPICAL SCAN DATA & DEFINITIONS
(ENGINE DATA) ............................................... 6E-79
TYPICAL SCAN DATA & DEFINITIONS
(O2 SENSOR DATA)........................................ 6E-81
MISCELLANEOUS TEST .................................. 6E-83
PLOTTING SNAPSHOT GRAPH ...................... 6E-85
Plotting Graph Flow Chart (Plotting graph
after obtaining vehicle information)................ 6E-86
Flow Chart for Snapshot Replay
(Plotting Graph) ............................................. 6E-87
SNAPSHOT DISPLAY WITH TIS2000.............. 6E-88
SERVICE PROGRAMMING SYSTEM (SPS).... 6E-91
HOW TO USE BREAKER BOX ........................ 6E-94
ON-BOARD DIAGNOSTIC (OBD) SYSTEM
CHECK ............................................................. 6E-97
NO CHECK ENGINE LAMP (MIL)..................... 6E-101
CHECK ENGINE LAMP (MIL) "ON" STEADY ... 6E-104
FUEL INJECTOR COIL TEST PROCEDURE
AND FUEL INJECTOR BALANCE
TEST PROCEDURE ......................................... 6E-106
FUEL SYSTEM ELECTRICAL TEST ................ 6E-111
FUEL SYSTEM DIAGNOSIS ............................. 6E-116
A/C SYSTEM CIRCUIT DIAGNOSIS ................ 6E-122
ECM DIAGNOSTIC TROUBLE CODES (DTC) 6E-130
MULTIPLE DTC SETS TROUBLESHOOTING
AIDS ................................................................. 6E-142
DTC P0101 (FLASH CODE 61) MASS
AIR FLOW SENSOR CIRCUIT
RANGE/PERFORMANCE ................................ 6E-146
DTC P0102 (FLASH CODE 61) MASS
AIR FLOW SENSOR CIRCUIT LOW INPUT ... 6E-149
DTC P0103 (FLASH CODE 61) MASS
AIR FLOW SENSOR CIRCUIT HIGH INPUT .. 6E-154
DTC P0112 (FLASH CODE 23) INTAKE AIR
TEMPERATURE (IAT) SENSOR LOW
INPUT ............................................................... 6E-158 DTC P0113 (FLASH CODE 23) INTAKE AIR
TEMPERATURE (IAT) SENSOR HIGH
INPUT ............................................................... 6E-163
DTC P0117 (FLASH CODE 14) ENGINE
COOLANT TEMPERATURER (ECT)
SENSOR LOW INPUT ..................................... 6E-168
DTC P0118 (FLASH CODE 14) ENGINE
COOLANT TEMPERATURER (ECT)
SENSOR HIGH INPUT..................................... 6E-173
DTC P0121 (FLASH CODE 21) THROTTLE
POSITION SENSOR (TPS) CIRCUIT
RANGE/PERFORMANCE ................................ 6E-179
DTC P0122 (FLASH CODE 21) THROTTLE
POSITION SENSOR (TPS) CIRCUIT
LOW INPUT ..................................................... 6E-183
DTC P0123 (FLASH CODE 21) THROTTLE
POSITION SENSOR (TPS) CIRCUIT
HIGH INPUT ..................................................... 6E-188
DTC P0131 (FLASH CODE 15) O2 SENSOR
CIRCUIT LOW VOLTAGE
(BANK 1 SENSOR 1) ....................................... 6E-193
DTC P0151 (FLASH CODE 15) O2 SENSOR
CIRCUIT LOW VOLTAGE
(BANK 2 SENSOR 1) ....................................... 6E-193
DTC P0132 (FLASH CODE 15) O2 SENSOR
CIRCUIT HIGH VOLTAGE
(BANK 1 SENSOR 1) ....................................... 6E-201
DTC P0152 (FLASH CODE 15) O2
SENSOR CIRCUIT HIGH VOLTAGE
(BANK 2 SENSOR 1) ....................................... 6E-201
DTC P0134 (FLASH CODE 15) O2 SENSOR
CIRCUIT NO ACTIVITY DETECTED
(BANK 1 SENSOR 1) ....................................... 6E-207
DTC P0154 (FLASH CODE 15) O2 SENSOR
CIRCUIT NO ACTIVITY
DETECTED (BANK 2 SENSOR 1) ................... 6E-207
DTC P0171 (FLASH CODE 44) O2 SENSOR
SYSTEM TOO LEAN (BANK 1) ....................... 6E-211
DTC P0174 (FLASH CODE 44) O2 SENSOR
SYSTEM TOO LEAN (BANK 2) ....................... 6E-211
DTC P0172 (FLASH CODE 45) O2 SENSOR
SYSTEM TOO RICH (BANK 1) ........................ 6E-216
DTC P0175 (FLASH CODE 45) O2 SENSOR
SYSTEM TOO RICH (BANK 2) ........................ 6E-216
DTC P1171 (FLASH CODE 44) FUEL
SUPPLY SYSTEM LEAN DURING POWER
ENRICHMENT (TYPE A) ................................. 6E-221
DTC P1172 (FLASH CODE 44) FUEL SUPPLY
SYSTEM LEAN DURING POWER
ENRICHMENT (TYPE B) ................................. 6E-221

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-7











Legend
(1) Injector #1 Cylinder
(2) Injector #3 Cylinder
(3) Injector #5 Cylinder
(4) EGR Valve
(5) Ignition Coil #1 Cylinder
(6) Ignition Coil #3 Cylinder
(7) Ignition Coil #5 Cylinder
(8) Engine Coolant Temperature (ECT) Sensor












Legend
(1) Injector #2 Cylinder
(2) Injector #4 Cylinder
(3) Injector #6 Cylinder
(4) Idle Air Control (IAC) Valve
(5) Throttle Position Sensor
(6) Ignition Coil #2 Cylinder
(7) Ignition Coil #4 Cylinder
(8) Ignition Coil #6 Cylinder
(9) Canister Purge Solenoid Valve

6E-28 3.5L ENGINE DRIVEABILITY AND EMISSIONS

No. Connector face No. Connector face
E-54

Ignition coil E-64

Oil pressure switch (P/STRG)
E-55

Ignition coil E-66
Duty solenoid
E-56

Ignition coil E-68

Throttle position sensor
E-57

Ignition coil E-69


Temperature sensor
E-58

Ignition coil E-70
IACV
E-59


Crank position sensor E-72

Engine earth-A
E-60

ECM-A E-73

Engine earth-A
E-61


ECM-B E-74
Engine earth-B
E-62

Cam position sensor E-76

EGR valve
E-63

MAF sensor E-77

O2 sensor RH-Front

6E-44 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Signal or Continuity Tester Position Pin
No.

B/Box
No.
Pin Function Wire
Color
Key SW
Off Key SW
On Engine
Idle Engine
2000rpmECM
Connection Range(+) (-)
A14 A14 No Connection - - - - - - - - -
A15 A15 No Connection - - - - - - - - -
A16 A16 No Connection - - - - - - - - -
A17 A17 No Connection - - - - - - - - -
A18 A18 No Connection - - - - - - - - -
A19 A19 Intake Air
Temperature
(IAT) Sensor
Signal YEL/
GRN Less than 1V0 deg. C: Approx. 3.5V / 20 deg. C: Approx.
2.5V / 40 deg. C: Approx. 1.6V / 60 deg. C:
0.9V / 80 deg. C: 0.6V Connect DC V A19 B39
A20 A20 No Connection - - - - - - - - -
A21 A21 Engine Coolant
Temperature
(ECT) Sensor
Signal BLU/
RED Less than 1V0 deg. C: Approx. 3.6V / 20 deg. C: Approx.
2.4V / 40 deg. C: Approx. 1.4V / 60 deg. C:
3.4V / 80 deg. C: 2.6V Connect DC V A21 A22
A22 A22 EGR Valve &
ECT Sensor
Ground YEL/
BLK Continuity
with ground - - - Connect Ohm A22 GND
A23 A23 Crank Position
(CKP) Sensor
Signal YEL - - Wave form or approx. 1.9V Connect AC V A23 A25
A24 A24 Crank Position
(CKP) Sensor &
EGR Valve +5V
Supply RED/
BLU Less than 1V Approx. 5V Connect DC V A24 A25
A25 A25 Crank Position
(CKP) Sensor
Ground YEL/
BLK Continuity
with ground - - - Connect Ohm A25 GND
A26 A26 No Connection - - - - - - - - -
A27 A27 No Connection - - - - - - - - -
A28 A28 ECM Main
Relay BLU/
RED While main
relay is
activated:
Less than 1V
Main relay is
not activated:
10-14V Less than 1V Connect DC V A28 GND
A29 A29 No Connection - - - - - - - - -
A30 A30 No. 5 Ignition
Coil RED/
YEL - - Wave form - - - -

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-53
Idle Air Control (IAC) Valve








Step
CoilAB CD
Coil A High
(EC M B13)On On
Coil A Low
(EC M B16)On On
Coil B High
(EC M B14)On On
Coil B Low
(EC M B17)On On

(IAC Valve Close Direction)
(IAC Valve Open Direction)



The idle air control valve (IAC) valve is two directional
and gives 2-way control. It has a stepping moto
r
capable of 256 steps, and also has 2 coils. With power
supply to the coils controlled steps by the engine control
module (ECM), the IAC valve's pintle is moved to adjus
t
idle speed, raising it for fast idle when cold or there is
extra load from the air conditioning or power steering.
By moving the pintle in (to decrease air flow) or out (to
increase air flow), a controlled amount of the air can
move around the throttle plate. If the engine speed is
too low, the engine control module (ECM) will retract the
IAC pintle, resulting in more air moving past the throttle
plate to increase the engine speed.
If the engine speed is too high, the engine control
module (ECM) will extend the IAC pintle, allowing less
air to move past the throttle plate, decreasing the
engine speed.

The IAC pintle valve moves in small step called counts.
During idle, the proper position of the IAC pintle is
calculated by the engine control module (ECM) based
on battery voltage, coolant temperature, engine load,
and engine speed.
If the engine speed drops below a specified value, and
the throttle plate is closed, the engine control module
(ECM) senses a near-stall condition. The engine control
module (ECM) will then calculate a new IAC pintle valve
position to prevent stalls. If the IAC valve is disconnected and reconnected with
the engine running, the idle speed will be wrong. In this
case, the IAC must be reset. The IAC resets when the
key is cycled "On" then "Off". When servicing the IAC, i
t
should only be disconnected or connected with the
ignition "Off".
The position of the IAC pintle valve affects engine start-
up and the idle characteristic of the vehicle.
If the IAC pintle is fully open, too much air will be
allowed into the manifold. This results in high idle
speed, along with possible hard starting and lean
air/fuel ratio.

Camshaft Position (CMP) Sensor








12
(1) Camshaft Position (CMP) Sensor
(2) EGR Valve


With the use of sequential multi-point fuel injection, a
hall element type camshaft position (CMP) is adopted to
provide information to be used in making decisions on
injection timing to each cylinder. It is mounted on the
rear of the left-hand cylinder head and sends signals to
the ECM.
One pulse is generated per two rotations of crankshaft.

6E-58 3.5L ENGINE DRIVEABILITY AND EMISSIONS
GENERAL DESCRIPTION FOR
ELECTRONIC IGNITION SYSTEM IGNITION
COILS & CONTROL
A separate coil-at-plug module is located at each spark
plug.
The coil-at-plug module is attached to the engine with
two screws. It is installed directly to the spark plug by an
electrical contact inside a rubber boot.
A three way connector provides 12 volts primary supply
from the ignition coil fuse, a ground switching trigge
r
line from the ECM, and ground.
The ignition control spark timing is the ECM's method o
f
controlling the spark advance and the ignition dwell.
The ignition control spark advance and the ignition dwell
are calculated by the ECM using the following inputs.

Engine speed

Crankshaft position (CKP) sensor

Camshaft position (CMP) sensor

Engine coolant temperature (ECT) sensor

Throttle position sensor

Park or neutral position switch

Vehicle speed sensor

ECM and ignition system supply voltage

Based on these sensor signal and engine load
information, the ECM sends 5V to each ignition coil
requiring ignition. This signal sets in the powe
r
transistor of the ignition coil to establish a grounding
circuit for the primary coil, applying battery voltage to
the primary coil.
At the ignition timing, the ECM stops sending the 5V
signal voltage. Under this condition the power transistor
of the ignition coil is set off to cut the battery voltage to
the primary coil, thereby causing a magnetic field
generated in the primary coil to collapse.
On this moment a line of magnetic force flows to the
secondary coil, and when this magnetic line crosses the
coil, high voltage induced by the secondary ignition
circuit to flow through the spark plug to the ground.

Ignition Control ECM Output
The ECM 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 coil module ("coil-at-plug") located at the
spark plug itself. When the ignition coil receives the
5-volt signal from the ECM, it provides a ground path fo
r
the B+ supply to the primary side of the coil-at -plug
module. This energizes the primary coil and creates a
magnetic field in the coil-at-plug module. When the
ECM shuts off the 5-volt signal to the ignition control
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 ECM and the ignition coil is
monitored for open circuits, shorts to voltage, and
shorts to ground. If the ECM 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

Spark Plug
Although worn or dirty spark plugs may give satisfactory
operation at idling speed, they frequency fail at highe
r
engine speeds. Faulty spark plugs may cause poor fuel
economy, power loss, loss of speed, hard starting and
generally poor engine performance. Follow the
scheduled maintenance service recommendations to
ensure satisfactory spark plug performance. Refer to
Maintenance and Lubrication.
Normal spark plug operation will result in brown to
grayish-tan deposits appearing on the insulator portion
of the spark plug. A small amount of red-brown, yellow,
and white powdery material may also be present on the
insulator tip around the center electrode. These
deposits are normal combustion by-products of fuels
and lubricating oils with additives. Some electrode wea
r
will also occur. Engines which are not running properly
are often referred to as “misfiring." This means the
ignition spark is not igniting the air/fuel mixture at the
proper time.
Spark plugs may also misfire due to fouling, excessive
gap, or a cracked or broken insulator. If misfiring
occurs before the recommended replacement interval,
locate and correct the cause.

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-59
Carbon fouling of the spark plug is indicated by dry,
black carbon (soot) deposits on the portion of the spark
plug in the cylinder. Excessive idling and slow speeds
under light engine loads can keep the spark plug
temperatures so low that these deposits are not burned
off. Very rich fuel mixtures or poor ignition system
output may also be the cause. Refer to DTC P0172.
Oil fouling of the spark plug is indicated by wet oily
deposits on the portion of the spark plug in the cylinder,
usually with little electrode wear. This may be caused by
oil during break-in of new or newly overhauled engines.
Deposit fouling of the spark plug occurs when the
normal red-brown, yellow or white deposits o
f
combustion by products become sufficient to cause
misfiring. In some cases, these deposits may melt and
form a shiny glaze on the insulator around the cente
r
electrode. If the fouling is found in only one or two
cylinders, valve stem clearances or intake valve seals
may be allowing excess lubricating oil to enter the
cylinder, particularly if the deposits are heavier on the
side of the spark plug facing the intake valve.



TS23995
Excessive gap means that the air space between the
center and the side electrodes at the bottom of the
spark plug is too wide for consistent firing. This may be
due to excessive wear of the electrode during use.
A
check of the gap size and comparison to the gap
specified for the vehicle in Maintenance and Lubrication
will tell if the gap is too wide. A spark plug gap that is
too small may cause an unstable idle condition.
Excessive gap wear can be an indication of continuous
operation at high speeds or with engine loads, causing
the spark to run too hot. Another possible cause is an
excessively lean fuel mixture.



TS23992
Low or high spark plug installation torque or improper
seating can result in the spark plug running too hot and
can cause excessive center electrode wear. The plug
and the cylinder head seats must be in good contact fo
r
proper heat transfer and spark plug cooling. Dirty or
damaged threads in the head or on the spark plug can
keep it from seating even though the proper torque is
applied. Once spark plugs are properly seated, tighten
them to the torque shown in the Specifications Table.
Low torque may result in poor contact of the seats due
to a loose spark plug. Over tightening may cause the
spark plug shell to be stretched and will result in poo
r
contact between the seats. In extreme cases, exhaus
t
blow-by and damage beyond simple gap wear may
occur.
Cracked or broken insulators may be the result o
f
improper installation, damage during spark plug heat
shock to the insulator material. Upper insulators can be
broken when a poorly fitting tool is used during
installation or removal, when the spark plug is hit from
the outside, or is dropped on a hard surface. Cracks in
the upper insulator may be inside the shell and no
t
visible. Also, the breakage may not cause problems
until oil or moisture penetrates the crack later.

6E-66 3.5L ENGINE DRIVEABILITY AND EMISSIONS
 Does it rely on some mechanical/vacuum
device to operate?

Physical:
 Where are the circuit components (componen
t
locators and wire harness routing diagrams):

Are there areas where wires could be
chafed or pinched (brackets or frames)?

Are there areas subjected to extreme
temperatures?

Are there areas subjected to vibration or
movement (engine, transmission or
suspension)?

Are there areas exposed to moisture, road
salt or other corrosives (battery acid, oil o
r
other fluids)?

Are there common mounting areas with
other systems/components?
 Have previous repairs been performed to
wiring, connectors, components or mounting
areas (causing pinched wires between panels
and drivetrain or suspension components
without causing and immediate problem)?
 Does the vehicle have aftermarket or dealer-
installed equipment (radios, telephone, etc.)

Step 2: Isolate the problem
At this point, you should have a good idea of what could
cause the present condition, as well as could not cause
the condition. Actions to take include the following:

Divide (and separate, where possible) the system
or circuit into smaller sections

Confine the problem to a smaller area of the
vehicle (start with main harness connections while
removing panels and trim as necessary in order to
eliminate large vehicle sections from furthe
r
investigation)

For two or more circuits that do not share a
common power or ground, concentrate on areas
where harnesses are routed together o
r
connectors are shared (refer to the following hints)

Hints
Though the symptoms may vary, basic electrical failures
are generally caused by:

Loose connections:
 Open/high resistance in terminals, splices,
connectors or grounds

Incorrect connector/harness routing (usually in
new vehicles or after a repair has been made):

 Open/high resistance in terminals, splices,
connectors of grounds

Corrosion and wire damage:
 Open/high resistance in terminals, splices,
connectors of grounds

Component failure:
 Opens/short and high resistance in relays,
modules, switches or loads


Aftermarket equipment affecting normal operation
of other systems You may isolate circuits by:

Unplugging connectors or removing a fuse to
separate one part of the circuit from another part

Operating shared circuits and eliminating those
that function normally from the suspect circuit

If only one component fails to operate, begin
testing at the component

If a number of components do no operate, begin
tests at the area of commonality (such as powe
r
sources, ground circuits, switches or majo
r
connectors)
What resources you should use
Whenever appropriate, you should use the following
resources to assist in the diagnostic process:

Service manual

Technical equipment (for data analysis)

Experience

Technical Assistance

Circuit testing tools
5d. Intermittent Diagnosis
By definition, an intermittent problem is one that does
not occur continuously and will occur when certain
conditions are met. All these conditions, however, may
not be obvious or currently known. Generally,
intermittents are caused by:

Faulty electrical connections and wiring

Malfunctioning components (such as sticking
relays, solenoids, etc.)

EMI/RFI (Electromagnetic/radio frequency
interference)

Aftermarket equipment
Intermittent diagnosis requires careful analysis of
suspected systems to help prevent replacing good
parts. This may involve using creativity and ingenuity to
interpret customer complaints and simulating all
external and internal system conditions to duplicate the
problem.

6E-70 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Fuel Quality
Fuel quality is not a new issue for the automotive
industry, but its potential for turning on the MIL (“Check
Engine" lamp) with OBD systems is new.
Fuel additives such as “dry gas" and “octane
enhancers" may affect the performance of the fuel. 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 sho
w
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 your vehicle
may cause driveability problems. Many of the majo
r
fuel companies advertise that using “premium" gasoline
will improve the performance of your vehicle. Mos
t
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 diagnostics have been calibrated to run
with OEM parts.
Aftermarket electronics, such as cellular phones,
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
(“Check Engine" 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
(“Check Engine" lamp).
Vehicle Marshaling
The transportation of new vehicles from the assembly
plant to the dealership can involve as many as 60 key
cycles within 5Km miles of driving. This type o
f
operation contributes to the fuel fouling of the spark
plugs and will turn on the MIL (“Check Engine" lamp).

Poor Vehicle Maintenance
The sensitivity of OBD diagnostics will cause the MIL
(“Check Engine" lamp) to turn on if the vehicle is no
t
maintained properly. Restricted air filters, fuel filters,
and crankcase deposits due to lack of oil changes o
r
improper oil viscosity can trigger actual vehicle faults
that were not previously monitored prior to OBD. Poo
r
vehicle maintenance can not be classified as a
“non-vehicle fault", but with the sensitivity of OBD
diagnostics, vehicle maintenance schedules must be
more closely followed.
Severe Vibration
The Misfire diagnostic measures small changes in the
rotational speed of the crankshaft. Severe driveline
vibrations in the vehicle, such as caused by an
excessive amount of mud on the wheels, can have the
same effect on crankshaft speed as misfire.
Related System Faults
Many of the OBD system diagnostics will not run if the
ECM detects a fault on a related system or component.
One example would be that if the ECM detected a
Misfire fault, the diagnostics on the catalytic converte
r
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 faul
t
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.
Maintenance Schedule
Refer to the Maintenance Schedule.
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 punches, cuts,
disconnects, and correct routing.

Inspect hoses that are difficult to see behind othe
r
components.

Inspect all wires in the engine compartment fo
r
proper connections, burned or chafed spots, pinched
wires, contact with sharp edges or contact with ho
t
exhaust manifolds or pipes.

6E-108 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Injector Coil Test Procedure (Steps 1-6) and Injector Balance Test Procedure
(Steps 7-11)

Step Action Value(s) YES NO
1
Was the “On-Board Diagnostic (OBD) System Check"
performed?
— Go to Step 2 Go to OBD
System Check
2 1. Turn the engine “OFF."
In order to prevent flooding of a single cylinder and
possible engine damage, relieve the fuel pressure
before performing the fuel injector coil test procedure.
2. Relieve the fuel pressure. Refer to Test
Description Number 2.
3. Connect the 5–8840–2618–0 Fuel Injector Tester
to B+ and ground, and to the 5–8840–2635–0
Injector Switch Box.
4. Connect the injector switch box to the gray fuel
injector harness connector located at the rear of
the air cleaner assembly.
5. Set the amperage supply selector switch on the
fuel injector tester to the “Coil Test" 0.5 amp
position.
6. Connect the leads from the Digital Voltmeter
(DVM) to the injector tester. Refer to the
illustrations associated with the test description.
7. Set the DVM to the tenths scale (0.0).
8. Observe the engine coolant temperature.
Is the engine coolant temperature within the specified
values? 10
C (50
F) to
35
C (95
F) Go to Step 3 Go to Step 5
3
1. Set injector switch box 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 switch box to the next 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 outside of the specified values? 5.7-6.6 V Go to Step 4 Go to Step 7
4 Replace the faulty fuel injector(s). Refer to Fuel
Injector.
Is the action complete? — Go to Step 7 —