Dodge Ram Truck 1500-2500-3500. Manual — part 358

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.

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 compressed air around coil base at cylinder head.

3. Prior to removing spark plug, spray compressed 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 Diagnostics 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 compressed air around coil base at cylinder head.

3. Prior to removing spark plug, spray compressed 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 Diagnostics 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 WARNINGS.

Before removing or disconnecting any spark plug cables, note their original position. Remove cables one-at-a-time.
To prevent ignition crossfire, spark plug cables MUST be placed in cable tray (routing loom) into their original posi-
tion. 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 compressed 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.

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5. Inspect spark plug condition. Refer to Diagnostics and Testing - Spark Plug Conditions.

CLEANING

CLEANING AND ADJUSTMENT

The plugs may be cleaned using commercially avail-
able spark plug cleaning equipment. After cleaning, 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.

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 electrodes 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 specifications.

3. Before installing ignition coil(s), check condition 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.

4.7L V-8

CAUTION: The 4.7L V–8 engine is equipped with copper core ground electrode spark plugs. They must be
replaced with the same type/number spark plug as the original. If another spark plug is substituted, pre-
ignition will result.

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 electrodes 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 specifications.

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3. Before installing ignition coil(s), check condition 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.

5.7L V-8

1. 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 electrodes can be damaged.

2. Start the spark plug into cylinder head by hand to avoid cross threading aluminum threads. To aid in installation,

attach a piece of rubber hose, or an old spark plug boot to spark plug.

3. The 5.7L V-8 is equipped with torque critical design spark plugs. Do not exceed 15 ft. lbs. torque. Tighten spark

plugs. Refer to torque specifications.

4. Before installing spark plug cables to either the spark plugs or coils, apply dielectric grease to inside of boots.

5. To prevent ignition crossfire, spark plug cables MUST be placed in cable tray (routing loom) into their original

position. Refer to Spark Plug Cable Removal for a graphic.

6. Install ignition coil(s) to necessary spark plugs. Refer to Ignition Coil Installation.

7. Install spark plug cables to remaining spark plugs. Remember to apply dielectric grease to inside of boots.

IGNITION COIL CAPACITOR

DESCRIPTION

One coil capacitor is used. It is located in the right-rear section of the engine compartment.

OPERATION

The coil capacitor(s) help dampen the amount of conducted electrical noise to the camshaft position sensor, crank-
shaft position sensor, and throttle position sensor. This noise is generated on the 12V supply wire to the ignition
coils and fuel injectors.

REMOVAL

The coil capacitor is located in the right-rear section of
the engine compartment. It is attached with a mount-
ing stud and nut.

1. Disconnect electrical connector (5) at capacitor.

2. Remove mounting nut and remove ground strap.

3. Remove capacitor.

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INSTALLATION

1. Position capacitor to mounting stud.

2. Position ground strap to mounting stud.

3. Tighten nut to 7 N·m (60 in. lbs.) torque.

4. Connect electrical connector to coil capacitor.

SPARK PLUG CABLE

DESCRIPTION

Spark plug cables are sometimes referred to as secondary ignition wires, or secondary ignition cables.

Plug cables are used only on the 5.7L V-8 engine.

OPERATION

The spark plug cables transfer electrical current from the ignition coil(s) and/or distributor, to individual spark plugs
at each cylinder. The resistive spark plug cables are of nonmetallic construction. The cables provide suppression of
radio frequency emissions from the ignition system.

Plug cables are used only on the 5.7L V-8 engine.

REMOVAL

REMOVAL

5.7L V-8

Spark plug cables on the 5.7L engine are paired on cylinders 1/6, 2/3, 4/7 and 5/8. Before removing or disconnect-
ing any spark plug cables, note their original position. Remove cables one-at-a-time. To prevent ignition crossfire,
spark plug cables MUST be placed in cable tray (routing loom) into their original position. The cable retention clips
must also be securly locked.

Before installing spark plug cables to either the spark plugs or coils, apply dielectric grease to inside of boots.

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