Oss DODGE RAM 2003 Service Repair Manual

HORN
TABLE OF CONTENTS
page page
HORN SYSTEM
DESCRIPTION..........................1
OPERATION............................1
DIAGNOSIS AND TESTING - HORN SYSTEM . . . 1
HORN
DIAGNOSIS AND TESTING - HORN..........1REMOVAL.............................2
INSTALLATION..........................2
HORN SWITCH
DESCRIPTION..........................2
DIAGNOSIS AND TESTING - HORN SWITCH . . . 2
HORN SYSTEM
DESCRIPTION
The dual-note horn system features dual electro-
magnetic horn units. The horn system includes the
following major components:
²Horn- The two horns are located on the left
side of the engine compartment below the Integrated
Power Module (IPM).
²Horn Switch- The horn switch is molded into
the driver airbag trim cover.
OPERATION
The horn system operates on battery current
received through a fuse in the Integrated Power
Module (IPM). The horn system circuit is designed so
that the system will remain operational, regardless
of the ignition switch position.
DIAGNOSIS AND TESTING - HORN SYSTEM
The most reliable, efficient, and accurate
means to diagnose the horn system requires the
use of a DRBIIItscan tool and the proper Diag-
nostic Procedures manual. The DRBIIItscan
tool can provide confirmation that the PCI data
bus is functional, that all of the electronic mod-
ules are sending and receiving the proper mes-
sages on the PCI data bus, and that the horns
are being sent the proper hard wired outputs
for them to perform their functions.
Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, details of wire
harness routing and retention, connector pin-out
information and location views for the various wire
harness connectors, splices and grounds.
In most cases, any problem involving continually
sounding horns can be quickly alleviated by removing
the horn fuse from the Integrated Power Module
(IPM).WARNING: DISABLE THE AIRBAG SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, SEAT BELT TENSIONER, SIDE
AIRBAG, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
HORN
DIAGNOSIS AND TESTING - HORN
The most reliable, efficient, and accurate
means to diagnose the horn system requires the
use of a DRBIIItscan tool and the proper Diag-
nostic Procedures manual. The DRBIIItscan
tool can provide confirmation that the PCI data
bus is functional, that all of the electronic mod-
ules are sending and receiving the proper mes-
sages on the PCI data bus, and that the horns
are being sent the proper hard wired outputs
for them to perform their functions.
Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, details of wire
harness routing and retention, connector pin-out
information and location views for the various wire
harness connectors, splices and grounds.
DRHORN 8H - 1

WARNING: DISABLE THE AIRBAG SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, SEAT BELT TENSIONER, SIDE
AIRBAG, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Disconnect the wire harness connectors from
the horns (Fig. 1).
(3) Remove mounting bolt and remove horns.
INSTALLATION
(1) Position horns and install mounting bolt.
Tighten the bolt to 10 N´m (85 in. lbs.).
(2) Connect wire harness connectors.
(3) Connect battery negative cable.
HORN SWITCH
DESCRIPTION
The horn switch is molded into the driver airbag.
The horn switch can not be serviced separately. For
service procedures, (Refer to 8 - ELECTRICAL/RE-
STRAINTS/DRIVER AIRBAG - REMOVAL).
DIAGNOSIS AND TESTING - HORN SWITCH
The most reliable, efficient, and accurate
means to diagnose the horn system requires the
use of a DRBIIItscan tool and the proper Diag-
nostic Procedures manual. The DRBIIItscan
tool can provide confirmation that the PCI data
bus is functional, that all of the electronic mod-
ules are sending and receiving the proper mes-
sages on the PCI data bus, and that the horns
are being sent the proper hard wired outputs
for them to perform their functions.
For complete circuit diagrams, refer to the appro-
priate wiring information. The wiring information
includes wiring diagrams, proper wire and connector
repair procedures, details of wire harness routing
and retention, connector pin-out information and
location views for the various wire harness connec-
tors, splices and grounds.
WARNING: DISABLE THE AIRBAG SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, SEAT BELT TENSIONER, SIDE
AIRBAG, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
Fig. 1 HORN
1 - WIRE HARNESS CONNECTORS
2 - HORNS
3 - MOUNTING BOLT
8H - 2 HORNDR
HORN (Continued)

IGNITION COIL RESISTANCE - 3.7L V-6
PRIMARY RESISTANCE
21-27ÉC (70-80ÉF)SECONDARY
RESISTANCE 21-27ÉC
(70-80ÉF)
0.6 - 0.9 Ohms 6,000 - 9,000 Ohms
IGNITION COIL RESISTANCE - 4.7L V-8
PRIMARY
RESISTANCE 21-27ÉC
(70-80ÉF)SECONDARY
RESISTANCE 21-27ÉC
(70-80ÉF)
0.6 - 0.9 Ohms 6,000 - 9,000 Ohms
IGNITION COIL RESISTANCE - 5.7L V-8
PRIMARY RESISTANCE @ 21-27ÉC (70-80ÉF)
0.558 - 0.682 Ohms
(Plus or Minus 10% @ 70-80É F)
IGNITION COIL RESISTANCE - 5.9L
COIL MANUFACTURERPRIMARY RESISTANCE
21-27ÉC (70-80ÉF)SECONDARY RESISTANCE 21-27ÉC
(70-80ÉF)
Diamond 0.97 - 1.18 Ohms 11,300 - 15,300 Ohms
Toyodenso 0.95 - 1.20 Ohms 11,300 - 13,300 Ohms
IGNITION COIL RESISTANCE ± 8.0L V-10
ENGINE
Primary Resistance: 0.53-0.65 Ohms. Test across the
primary connector. Refer to text for test procedures.
Secondary Resistance: 10.9-14.7K Ohms. Test across
the individual coil towers. Refer to text for test
procedures.
IGNITION TIMING
Ignition timing is not adjustable on any engine.
AUTOMATIC SHUT DOWN
RELAY
DESCRIPTION - PCM OUTPUT
The 5±pin, 12±volt, Automatic Shutdown (ASD)
relay is located in the Power Distribution Center
(PDC). Refer to label on PDC cover for relay location.
OPERATION
OPERATION - PCM OUTPUT
The ASD relay supplies battery voltage (12+ volts)
to the fuel injectors and ignition coil(s). With certain
emissions packages it also supplies 12±volts to the
oxygen sensor heating elements.The ground circuit for the coil within the ASD
relay is controlled by the Powertrain Control Module
(PCM). The PCM operates the ASD relay by switch-
ing its ground circuit on and off.
The ASD relay will be shut±down, meaning the
12±volt power supply to the ASD relay will be de-ac-
tivated by the PCM if:
²the ignition key is left in the ON position. This
is if the engine has not been running for approxi-
mately 1.8 seconds.
²there is a crankshaft position sensor signal to
the PCM that is lower than pre-determined values.
OPERATION - ASD SENSE - PCM INPUT
A 12 volt signal at this input indicates to the PCM
that the ASD has been activated. The relay is used to
connect the oxygen sensor heater element, ignition
coil and fuel injectors to 12 volt + power supply.
This input is used only to sense that the ASD relay
is energized. If the Powertrain Control Module
(PCM) does not see 12 volts at this input when the
ASD should be activated, it will set a Diagnostic
Trouble Code (DTC).
8I - 6 IGNITION CONTROLDR
IGNITION CONTROL (Continued)

8.0L V±10
If Replacing Old Sensor With Original
The camshaft position sensor is located on the tim-
ing chain case/cover on the left-front side of the
engine (Fig. 18).
When installing a used camshaft position sensor,
the sensor depth must be adjusted to prevent contact
with the camshaft gear (sprocket).
(1) Observe the face of the sensor. If any of the
original rib material remains (Fig. 19), it must be cut
down flush to the face of the sensor with a razor
knife. Remove only enough of the rib material until
the face of the sensor is flat. Do not remove more
material than necessary as damage to sensor may
result. Due to a high magnetic field and possible elec-
trical damage to the sensor, never use an electric
grinder to remove material from sensor.
(2) From the parts department, obtain a peel-and-
stick paper spacer (Fig. 19). These special paper
spacers are of a certain thickness and are to be used
as a tool to set sensor depth.
(3) Clean the face of sensor and apply paper
spacer (Fig. 19).
(4) Apply a small amount of engine oil to the sen-
sor o-ring (Fig. 20).
A low and high area are machined into the cam-
shaft drive gear (Fig. 21). The sensor is positioned in
the timing gear cover so that a small air gap (Fig.
21) exists between the face of sensor and the high
machined area of cam gear.
Before the sensor is installed, the cam gear may
have to be rotated. This is to allow the high
machined area on the gear to be directly in front of
the sensor mounting hole opening on the timing gear
cover.
Do not install sensor with gear positioned at
low area (Fig. 22) or (Fig. 21). When the engine
is started, the sensor will be broken.
(5) Using a 1/2 in. wide metal ruler, measure the
distance from the cam gear to the face of the sensor
mounting hole opening on the timing gear cover (Fig.
22).
(6) If the dimension is approximately 1.818 inches,
it is OK to install sensor. Proceed to step Step 9.
(7) If the dimension is approximately 2.018 inches,
the cam gear will have to be rotated.
(8) Attach a socket to the vibration damper mount-
ing bolt and rotate engine until the 1.818 inch
dimension is attained.
(9) Install the sensor into the timing case/cover
with a slight rocking action until the paper spacer
contacts the camshaft gear. Do not install the sensor
mounting bolt. Do not twist the sensor into position
as damage to the o-ring or tearing of the paper
spacer may result.(10) Scratch a scribe line into the timing chain
case/cover to indicate depth of sensor (Fig. 20).
(11) Remove the sensor from timing chain case/
cover.
(12) Remove paper spacer from sensor. This step
must be followed to prevent the paper spacer from
getting into the engine lubrication system.
(13) Again, apply a small amount of engine oil to
sensor o-ring.
(14) Again, install the sensor into the timing case/
cover with a slight rocking action until the sensor is
aligned to scribe line.
(15) Install sensor mounting bolt and tighten to 6
N´m (50 in. lbs.) torque.
(16) Connect engine wiring harness to sensor.
Replacing With a New Sensor
(1) Apply a small amount of engine oil to the sen-
sor o-ring (Fig. 20).
A low and high area are machined into the cam-
shaft drive gear (Fig. 21). The sensor is positioned in
the timing gear cover so that a small air gap (Fig.
21) exists between the face of sensor and the high
machined area of cam gear.
Before the sensor is installed, the cam gear may
have to be rotated. This is to allow the high
machined area on the gear to be directly in front of
the sensor mounting hole opening on the timing gear
cover.
Fig. 21 SENSOR OPERATION ± 8.0L V-10 ENGINE
1 - CAM DRIVE GEAR
2 - LOW MACHINED AREA
3 - HIGH MACHINED AREA
4 - CAMSHAFT POSITION SENSOR
5 - AIR GAP
DRIGNITION CONTROL 8I - 15
CAMSHAFT POSITION SENSOR (Continued)

INSTALLATION
If engine has been cranked while distributor is
removed, establish the relationship between distribu-
tor shaft and number one piston position as follows:
Rotate crankshaft in a clockwise direction, as
viewed from front, until number one cylinder piston
is at top of compression stroke (compression should
be felt on finger with number one spark plug
removed). Then continue to slowly rotate engine
clockwise until indicating mark (Fig. 24) is aligned to
0 degree (TDC) mark on timing chain cover.
(1) Clean top of cylinder block for a good seal
between distributor base and block.
(2) Lightly oil the rubber o-ring seal on the distrib-
utor housing.
(3) Install rotor to distributor shaft.
(4) Position distributor into engine to its original
position. Engage tongue of distributor shaft with slot
in distributor oil pump drive gear. Position rotor to
the number one spark plug cable position.
(5) Install distributor holddown clamp and clamp
bolt. Do not tighten bolt at this time.
(6) Rotate the distributor housing until rotor is
aligned to CYL. NO. 1 alignment mark on the cam-
shaft position sensor (Fig. 25).
(7) Tighten clamp holddown bolt (Fig. 26) to 22.5
N´m (200 in. lbs.) torque.
(8) Connect camshaft position sensor wiring har-
ness to main engine harness.
(9) Install distributor cap. Tighten mounting
screws.
(10) Refer to the following, Checking Distributor
Position.
Checking Distributor Position
To verify correct distributor rotational position, the
DRB scan tool must be used.
WARNING: WHEN PERFORMING THE FOLLOWING
TEST, THE ENGINE WILL BE RUNNING. BE CARE-
FUL NOT TO STAND IN LINE WITH THE FAN
BLADES OR FAN BELT. DO NOT WEAR LOOSE
CLOTHING.
(1) Connect DRB scan tool to data link connector.
The data link connector is located in passenger com-
partment, below and to left of steering column.
(2) Gain access to SET SYNC screen on DRB.
(3) Follow directions on DRB screen and start
engine. Bring to operating temperature (engine must
be in ªclosed loopº mode).
(4) With engine running atidle speed, the words
IN RANGE should appear on screen along with 0É.
This indicates correct distributor position.(5) If a plus (+) or a minus (-) is displayed next to
degree number, and/or the degree displayed is not
zero, loosen but do not remove distributor holddown
clamp bolt. Rotate distributor until IN RANGE
appears on screen. Continue to rotate distributor
until achieving as close to 0É as possible. After
adjustment, tighten clamp bolt to 22.5 N´m (200 in.
lbs.) torque.
Do not attempt to adjust ignition timing using this
method. Rotating distributor will have no effect on
ignition timing. All ignition timing values are con-
trolled by Powertrain Control Module (PCM).
After testing, install air cleaner tubing.
DISTRIBUTOR CAP
DIAGNOSIS AND TESTING - DISTRIBUTOR
CAP - 5.9L V-8
Remove the distributor cap and wipe it clean with
a dry lint free cloth. Visually inspect the cap for
cracks, carbon paths, broken towers or damaged
rotor button (Fig. 27) or (Fig. 28). Also check for
white deposits on the inside (caused by condensation
entering the cap through cracks). Replace any cap
that displays charred or eroded terminals. The
machined surface of a terminal end (faces toward
rotor) will indicate some evidence of erosion from
normal operation. Examine the terminal ends for evi-
dence of mechanical interference with the rotor tip.
Fig. 27 CAP INSPECTIONÐEXTERNALÐTYPICAL
1 - BROKEN TOWER
2 - DISTRIBUTOR CAP
3 - CARBON PATH
4 - CRACK
8I - 18 IGNITION CONTROLDR
DISTRIBUTOR (Continued)

The PCM adjusts ignition timing based on inputs it
receives from:
²The engine coolant temperature sensor
²The crankshaft position sensor (engine speed)
²The camshaft position sensor (crankshaft posi-
tion)
²The manifold absolute pressure (MAP) sensor
²The throttle position sensor
²Transmission gear selection
REMOVAL
3.7L V-6
An individual ignition coil is used for each spark
plug (Fig. 30). The coil fits into machined holes in the
cylinder head. A mounting stud/nut secures each coil
to the top of the intake manifold (Fig. 31). The bot-
tom of the coil is equipped with a rubber boot to seal
the spark plug to the coil. Inside each rubber boot is
a spring. The spring is used for a mechanical contact
between the coil and the top of the spark plug. These
rubber boots and springs are a permanent part of the
coil and are not serviced separately. An o-ring (Fig.
30) is used to seal the coil at the opening into the cyl-
inder head.
(1) Depending on which coil is being removed, the
throttle body air intake tube or intake box may need
to be removed to gain access to coil.
(2) Disconnect electrical connector from coil by
pushing downward on release lock on top of connec-
tor and pull connector from coil.
(3) Clean area at base of coil with compressed air
before removal.
(4) Remove coil mounting nut from mounting stud
(Fig. 31).
(5) Carefully pull up coil from cylinder head open-
ing with a slight twisting action.
(6) Remove coil from vehicle.
4.7L V-8
An individual ignition coil is used for each spark
plug (Fig. 30). The coil fits into machined holes in the
cylinder head. A mounting stud/nut secures each coil
to the top of the intake manifold (Fig. 32). The bot-
tom of the coil is equipped with a rubber boot to seal
the spark plug to the coil. Inside each rubber boot is
a spring. The spring is used for a mechanical contact
between the coil and the top of the spark plug. These
rubber boots and springs are a permanent part of the
coil and are not serviced separately. An o-ring (Fig.
30) is used to seal the coil at the opening into the cyl-
inder head.
(1) Depending on which coil is being removed, the
throttle body air intake tube or intake box may need
to be removed to gain access to coil.(2) Disconnect electrical connector (Fig. 32) from
coil by pushing downward on release lock on top of
connector and pull connector from coil.
(3) Clean area at base of coil with compressed air
before removal.
(4) Remove coil mounting nut from mounting stud
(Fig. 32).
(5) Carefully pull up coil from cylinder head open-
ing with a slight twisting action.
(6) Remove coil from vehicle.
5.7L V-8
Before removing or disconnecting any spark plug
cables, note their original position. Remove cables
one-at-a-time. To prevent ignition crossfire, spark
plug cablesMUSTbe placed in cable tray (routing
loom) into their original position.
An individual ignition coil (Fig. 33) is used at each
cylinder. The coil mounts to the top of the valve cover
with 2 bolts (Fig. 34). The bottom of the coil is
equipped with a rubber boot to seal the spark plug to
the coil. Inside each rubber boot is a spring. The
spring is used for a mechanical contact between the
coil and the top of the spark plug.
(1) Depending on which coil is being removed, the
throttle body air intake tube or intake box may need
to be removed to gain access to coil.
(2) Unlock electrical connector (Fig. 34) by moving
slide lock first. Press on release lock (Fig. 34) while
pulling electrical connector from coil.
(3) Disconnect secondary high-voltage cable from
coil with a twisting action.
(4) Clean area at base of coil with compressed air
before removal.
(5) Remove 2 mounting bolts (note that mounting
bolts are retained to coil).
(6) Carefully pull up coil from cylinder head open-
ing with a slight twisting action.
(7) Remove coil from vehicle.
(8) Before installing spark plug cables to either the
spark plugs or coils, or before installing a coil to a
spark plug, apply dielectric grease to inside of boots.
5.9L V-8
The coil is not oil filled. The coil windings are
embedded in an epoxy compound. This provides heat
and vibration resistance that allows the coil to be
mounted on the engine. If the coil is replaced, it must
be replaced with the same type.
5.9L V-8 LDC-Gas Engines: The coil is mounted to
a bracket that is bolted to the front of the right
engine cylinder head (Fig. 35). This bracket is
mounted on top of the automatic belt tensioner
bracket using common bolts.
DRIGNITION CONTROL 8I - 23
IGNITION COIL (Continued)

WARNING: 5.9L V-8 LDC-GAS ENGINES: DO NOT
REMOVE THE COIL MOUNTING BRACKET-TO-CYL-
INDER HEAD MOUNTING BOLTS. THE COIL
MOUNTING BRACKET IS UNDER ACCESSORY
DRIVE BELT TENSION. IF THIS BRACKET IS TO BE
REMOVED FOR ANY REASON, ALL BELT TENSION
MUST FIRST BE RELIEVED. REFER TO THE BELT
SECTION OF GROUP 7, COOLING SYSTEM.
5.9L V-8 HDC-Gas Engine: The coil is mounted to
a bracket that is bolted to the air injection pump
(AIR pump) mounting bracket (Fig. 36).
(1) Disconnect primary coil connector from ignition
coil.
(2) Disconnect secondary cable from ignition coil.
(3) Remove ignition coil from coil mounting
bracket (two bolts).
8.0L V-10
Two separate coil packs containing a total of five
independent coils are attached to a common mount-
ing bracket located above the right engine valve
cover (Fig. 37). The front and rear coil packs can be
serviced separately.
(1) Depending on which coil is being removed, the
throttle body air intake tube or intake box may need
to be removed to gain access to coils.
(2) Remove secondary spark plug cables from coil
packs. Note position of cables before removal.
(3) Disconnect primary wiring harness connectors
at coil packs.
(4) Remove four (4) coil pack-to-coil mounting
bracket bolts for coil pack being serviced (Fig. 37).
(5) Remove coil(s) from mounting bracket.
INSTALLATION
3.7L V-6
(1) Using compressed air, blow out any dirt or con-
taminants from around top of spark plug.
(2) Check condition of coil o-ring and replace as
necessary. To aid in coil installation, apply silicone to
coil o-ring.
(3) Position ignition coil into cylinder head opening
and push onto spark plug. Do this while guiding coil
base over mounting stud.
(4) Install coil mounting stud nut. Refer to torque
specifications.
(5) Connect electrical connector to coil by snapping
into position.
(6) If necessary, install throttle body air tube.
4.7L V-8
(1) Using compressed air, blow out any dirt or con-
taminants from around top of spark plug.
(2) Check condition of coil o-ring and replace as
necessary. To aid in coil installation, apply silicone to
coil o-ring.
(3) Position ignition coil into cylinder head opening
and push onto spark plug. Do this while guiding coil
base over mounting stud.
(4) Install coil mounting stud nut. Refer to torque
specifications.
(5) Connect electrical connector to coil by snapping
into position.
(6) If necessary, install throttle body air tube.
5.7L V-8
(1) Using compressed air, blow out any dirt or con-
taminants from around top of spark plug.
(2) Before installing spark plug cables to either the
spark plugs or coils, or before installing a coil to a
spark plug, apply dielectric grease to inside of boots.
(3) Position ignition coil into cylinder head opening
and push onto spark plug. Twist coil into position.
(4) Install 2 coil mounting bolts. Refer to torque
specifications.
(5) Connect electrical connector to coil by snapping
into position.
(6) Install cable to coil. To prevent ignition cross-
fire, spark plug cablesMUSTbe placed in cable tray
(routing loom) into their original position. Refer to
Spark Plug Cable Removal for a graphic.
(7) If necessary, install throttle body air tube.
5.9L V-8
The ignition coil is an epoxy filled type. If the coil
is replaced, it must be replaced with the same type.
(1) Install ignition coil to coil bracket. If nuts and
bolts are used to secure coil to coil bracket, tighten to
11 N´m (100 in. lbs.) torque. If coil mounting bracket
has been tapped for coil mounting bolts, tighten bolts
to 5 N´m (50 in. lbs.) torque.
(2) Connect all wiring to ignition coil.
8.0L V-10
(1) Position coil packs to mounting bracket (prima-
ry wiring connectors face downward).
(2) Install coil pack mounting bolts. Tighten bolts
to 10 N´m (90 in. lbs.) torque.
(3) Install coil pack-to-engine mounting bracket (if
necessary).
(4) Connect primary wiring connectors to coil
packs (four wire connector to front coil pack and
three wire connector to rear coil pack).
(5) Connect secondary spark plug cables to coil
packs. Refer to (Fig. 38) for correct cable order.
8I - 24 IGNITION CONTROLDR
IGNITION COIL (Continued)

NOTE: Over or under tightening the sensor mount-
ing bolts will affect knock sensor performance, pos-
sibly causing improper spark control. Always use
the specified torque when installing the knock sen-
sors. The torque for the knock senor bolt is rela-
tively light for an 8mm bolt.
NOTE: Note foam strip on bolt threads. This foam is
used only to retain the bolts to sensors for plant
assembly. It is not used as a sealant. Do not apply
any adhesive, sealant or thread locking compound
to these bolts.
(3) Install and tighten mounting bolts. Refer to
torque specification.
(4) Install intake manifold. Refer to Engine sec-
tion.
(5) Connect knock sensor wiring harness to engine
harness at rear of intake manifold.
5.7L V-8
(1) Thoroughly clean knock sensor mounting hole.
(2) Install sensor into cylinder block.
NOTE: Over or under tightening the sensor mount-
ing bolts will affect knock sensor performance, pos-
sibly causing improper spark control. Always use
the specified torque when installing the knock sen-
sors. The torque for the knock senor bolt is rela-
tively light for an 8mm bolt.
NOTE: Note foam strip on bolt threads. This foam is
used only to retain the bolts to sensors for plant
assembly. It is not used as a sealant. Do not apply
any adhesive, sealant or thread locking compound
to these bolts.
(3) Install and tighten mounting bolt. Refer to
torque specification.
(4) Install electrical connector to sensor.
SPARK PLUG
DESCRIPTION
Resistor type spark plugs are used on all engines.
Sixteen spark plugs (2 per cylinder) are used with
5.7L V-8 engines.
DIAGNOSIS AND TESTING - SPARK PLUG
CONDITIONS
To prevent possible pre-ignition and/or mechanical
engine damage, the correct type/heat range/number
spark plug must be used.
Always use the recommended torque when tighten-
ing spark plugs. Incorrect torque can distort the
spark plug and change plug gap. It can also pull the
plug threads and do possible damage to both the
spark plug and the cylinder head.
Remove the spark plugs and examine them for
burned electrodes and fouled, cracked or broken por-
celain insulators. Keep plugs arranged in the order
in which they were removed from the engine. A sin-
gle plug displaying an abnormal condition indicates
that a problem exists in the corresponding cylinder.
Replace spark plugs at the intervals recommended in
the Lubrication and Maintenance section.
Spark plugs that have low mileage may be cleaned
and reused if not otherwise defective, carbon or oil
fouled.
CAUTION: Never use a motorized wire wheel brush
to clean the spark plugs. Metallic deposits will
remain on the spark plug insulator and will cause
plug misfire.
Spark plug resistance values range from 6,000 to
20,000 ohms (when checked with at least a 1000 volt
spark plug tester).Do not use an ohmmeter to
check the resistance values of the spark plugs.
Inaccurate readings will result.
NORMAL OPERATING
The few deposits present on the spark plug will
probably be light tan or slightly gray in color. This is
evident with most grades of commercial gasoline
(Fig. 42). There will not be evidence of electrode
burning. Gap growth will not average more than
approximately 0.025 mm (.001 in) per 3200 km (2000
miles) of operation. Spark plugs that have normal
wear can usually be cleaned, have the electrodes
filed, have the gap set and then be installed.
Some fuel refiners in several areas of the United
States have introduced a manganese additive (MMT)
for unleaded fuel. During combustion, fuel with MMT
causes the entire tip of the spark plug to be coated
with a rust colored deposit. This rust color can be
misdiagnosed as being caused by coolant in the com-
bustion chamber. Spark plug performance may be
affected by MMT deposits.
DRIGNITION CONTROL 8I - 27
KNOCK SENSOR (Continued)

REMOVAL
3.7L V-6
Each individual spark plug is located under each
ignition coil. Each individual ignition coil must be
removed to gain access to each spark plug. Refer to
Ignition Coil Removal/Installation.
(1) Remove necessary air filter tubing at throttle
body.
(2) Prior to removing ignition coil, spray com-
pressed air around coil base at cylinder head.
(3) Prior to removing spark plug, spray com-
pressed air into cylinder head opening. This will help
prevent foreign material from entering combustion
chamber.
(4) Remove spark plug from cylinder head using a
quality socket with a rubber or foam insert. Also
check condition of ignition coil o-ring and replace as
necessary.
(5) Inspect spark plug condition. Refer to Diagnos-
tics and Testing - Spark Plug Conditions.
4.7L V-8
Each individual spark plug is located under each
ignition coil. Each individual ignition coil must be
removed to gain access to each spark plug. Refer to
Ignition Coil Removal/Installation.
(1) Remove necessary air filter tubing at throttle
body.
(2) Prior to removing ignition coil, spray com-
pressed air around coil base at cylinder head.
(3) Prior to removing spark plug, spray com-
pressed air into cylinder head opening. This will help
prevent foreign material from entering combustion
chamber.
(4) Remove spark plug from cylinder head using a
quality socket with a rubber or foam insert. Also
check condition of ignition coil o-ring and replace as
necessary.
(5) Inspect spark plug condition. Refer to Diagnos-
tics and Testing - Spark Plug Conditions.
5.7L V-8
Eight of the 16 spark plugs are located under an
ignition coil; the other 8 are not. If spark plug being
removed is under coil, coil must be removed to gain
access to spark plug. Refer to Ignition Coil Removal/
Installation and observe all CAUTIONS and WARN-
INGS.
Before removing or disconnecting any spark plug
cables, note their original position. Remove cables
one-at-a-time. To prevent ignition crossfire, spark
plug cablesMUSTbe placed in cable tray (routing
loom) into their original position. Refer to Spark Plug
Cable Removal for a graphic.Before installing spark plug cables to either the
spark plugs or coils, apply dielectric grease to inside
of boots.
(1) Remove necessary air filter tubing at throttle
body.
(2) Prior to removing ignition coil (if coil removal
is necessary), spray compressed air around coil base
at cylinder head cover.
(3) Prior to removing spark plug, spray com-
pressed air into cylinder head opening. This will help
prevent foreign material from entering combustion
chamber.
(4) Remove spark plug from cylinder head using a
quality socket with a rubber or foam insert.
(5) Inspect spark plug condition. Refer to Diagnos-
tics and Testing - Spark Plug Conditions.
5.9L V-8
On 5.9L V-8 engines, spark plug cable heat shields
are pressed into the cylinder head to surround each
cable boot and spark plug (Fig. 49).
(1) Always remove spark plug or ignition coil
cables by grasping at the cable boot (Fig. 50). Turn
the cable boot 1/2 turn and pull straight back in a
steady motion. Never pull directly on the cable.
Internal damage to cable will result.
(2) Prior to removing the spark plug, spray com-
pressed air around the spark plug hole and the area
around the spark plug. This will help prevent foreign
material from entering the combustion chamber.
(3) Remove the spark plug using a quality socket
with a rubber or foam insert.
(4) Inspect the spark plug condition. Refer to Diag-
nostics and Testing - Spark Plug Conditions.
Fig. 49 HEAT SHIELDS - 5.9L V-8
1 - AIR GAP
2 - SPARK PLUG BOOT HEAT SHIELD
8I - 30 IGNITION CONTROLDR
SPARK PLUG (Continued)

8.0L V-10
(1) Always remove spark plug or ignition coil
cables by grasping at the cable boot (Fig. 50). Turn
the cable boot 1/2 turn and pull straight back in a
steady motion. Never pull directly on the cable.
Internal damage to cable will result.
(2) Prior to removing the spark plug, spray com-
pressed air around the spark plug hole and the area
around the spark plug. This will help prevent foreign
material from entering the combustion chamber.
(3) Remove the spark plug using a quality socket
with a rubber or foam insert.
(4) Inspect the spark plug condition. Refer to Diag-
nostics and Testing - Spark Plug Conditions.
CLEANING
CLEANING AND ADJUSTMENT
The plugs may be cleaned using commercially
available spark plug cleaning equipment. After clean-
ing, file center electrode flat with a small point file or
jewelers file before adjusting gap.
CAUTION: Never use a motorized wire wheel brush
to clean spark plugs. Metallic deposits will remain
on spark plug insulator and will cause plug misfire.
Adjust spark plug gap with a gap gauging tool
(Fig. 51).
INSTALLATION
3.7L V-6
Special care should be taken when installing spark
plugs into the cylinder head spark plug wells. Be
sure the plugs do not drop into the plug wells as elec-
trodes can be damaged.
Always tighten spark plugs to the specified torque.
Over tightening can cause distortion resulting in a
change in the spark plug gap or a cracked porcelain
insulator.
(1) Start the spark plug into the cylinder head by
hand to avoid cross threading.
(2) Tighten spark plugs. Refer to torque specifica-
tions.
(3) Before installing ignition coil(s), check condi-
tion of coil o-ring and replace as necessary. To aid in
coil installation, apply silicone to coil o-ring.
(4) Install ignition coil(s). Refer to Ignition Coil
Removal/Installation.
Fig. 50 CABLE REMOVAL - 5.9L / 8.0L
1 - SPARK PLUG CABLE AND BOOT
2 - SPARK PLUG BOOT PULLER
3 - TWIST AND PULL
4 - SPARK PLUG
Fig. 51 SETTING SPARK PLUG GAP - TYPICAL
1 - GAUGE TOOL
2 - SPARK PLUG
DRIGNITION CONTROL 8I - 31
SPARK PLUG (Continued)