Dodge ZB 2005, Service Manual

Page: 284 / 1873

SPARK PLUG
DESCRIPTION
The 8.3L V-10 engine uses resistor spark plugs.
They have resistance values of 6,000 to 20,000 ohms
when checked with at least a 1000 volt tester.
OPERATION
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. An iso-
lated plug displaying an abnormal condition indicates
that a problem exists in the corresponding cylinder.
Spark plugs that have low mileage may be cleaned
and reused if not otherwise defective. Adjust the gap
between the electrodes (Fig. 11) to the dimensions
specified in the chart at the end of this section.
Always tighten spark plugs to the specified torque.
Over tightening can cause distortion resulting in a
change in the spark plug gap. Tighten spark plugs to
27 N·m (20 ft. lbs.) torque.
REMOVAL
Failure to route the cables properly could cause the
radio to reproduce ignition noise, cross ignition of the
spark plugs or short circuit the cables to ground.
Always remove the spark plug cable by grasping
the top of the spark plug insulator, turning the boot
1/2 turn and pulling straight up in a steady motion.
(1) Remove the spark plug using a quality socket
with a rubber or foam insert.
INSTALLATION
Failure to route the cables properly could cause the
radio to reproduce ignition noise, cross ignition of the
spark plugs or short circuit the cables to ground.
(1) To avoid cross threading, start the spark plug
into the cylinder head by hand.
(2) Tighten spark plugs to 27 N·m (20 ft. lbs.)
torque.
(3) Install spark plug insulators over spark plugs.
SPARK PLUG CABLE
DESCRIPTION
Spark Plug cables are sometimes referred to as
secondary ignition wires. The wires transfer electri-
cal current from the electronic ignition coils to the
individual spark plug at each cylinder. The nonmetal-
lic spark plug cables have built in resistance. The
cables provide suppression of radio frequency emis-
sions from the ignition system.
Check the spark plug cable connections for good
contact at the coil or coil pack and at the spark
plugs. Terminals should be fully seated with audible
click. The nipples and spark plug covers should be in
good condition. Nipples should fit tightly on the coil
or coil pack and spark plug cover should fit tight
around spark plug insulators. Loose cable connec-
tions can cause ignition malfunctions, corroding, and
increasing resistance. To maintain proper sealing
at the terminal connections, the connections
should not be broken unless testing indicates
high resistance, an open circuit or other dam-
age.
Clean high tension cables with a cloth moistened
with a non-flammable solvent and wipe dry. Check
for brittle or cracked insulation. Plastic clips in vari-
ous locations protect the cables from damage. When
the cables are replaced the clips must be used to pre-
vent damage to the cables.
REMOVAL
Failure to route the cables properly could cause the
radio to reproduce ignition noise, cross ignition of the
spark plugs or short circuit the cables to ground.
(1) Release the fuel pressure, refer to the Fuel
Pressure Release procedure in the Fuel Delivery sec-
tion.
(2) Disconnect the negative battery cable.
(3) Remove the air cleaner assembly, refer to the
Engine/Air Intake section for more information.
(4) Remove the Intake Manifold, refer to the
Engine/Manifolds/Intake Manifold for more informa-
tion.
(5) Use the following procedure when removing the
high tension cable from the spark plug. Grasp the
Fig. 11 Setting Spark Plug Electrode Gap—Typical
1 - TAPER GAUGE
ZB
IGNITION CONTROL 8I - 7