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Dodge Ram Truck 1500-2500-3500. Manual - part 357

7. Remove the 4 bolts.

8. Remove ignition coil.

INSTALLATION

3.7L V-6

1. Using compressed air, blow out any dirt or contaminants 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 contaminants 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 contaminants 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 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.

7. If necessary, install throttle body air tube.

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IGNITION CONTROL - SERVICE INFORMATION

DR/DH

8.3L - SRT-10

The system uses two epoxy filled coil packs mounted
on engine block post under the intake manifold. The
rear coil pack, contains 3 separate coils and fires cyl-
inders 1, 2, 3, 4, 6, and 7. The front coil pack, con-
tains 2 individual coils and fires cylinders 5, 8, 9, and
10.

1. Install coil packs. Tighten mounting screws to 11

N·m (95 in. lbs.) torque.

2. Install ignition cables to ignition coil.

3. Connect and lock the electrical connector at the

ignition coils and.

4. Install Intake Manifold, refer to the Engine/Mani-

folds/Intake Manifold for more information.

5. Install Air Cleaner Assembly, refer to the Engine/Air

Intake section for more information.

6. Connect the negative battery cable.

7. Use a diagnostic scan tool to pressurize the fuel

system. Check for leaks.

SENSOR-KNOCK

DESCRIPTION

The sensors are used only with 3.7L V-6, 4.7L V-8 and 5.7L V-8 engines. On 3.7L V-6 and 4.7L V-8 engines, the 2
knock sensors are bolted into the cylinder block under the intake manifold.

On 5.7L V-8 engines, 2 knock sensors are also used. These are bolted into each side of the cylinder block (outside)
under the exhaust manifold.

OPERATION

3.7L V-6 / 4.7L V-8 / 5.7L V-8 Engines Only

Two knock sensors are used; one for each cylinder bank. When the knock sensor detects a knock in one of the
cylinders on the corresponding bank, it sends an input signal to the Powertrain Control Module (PCM). In response,
the PCM retards ignition timing for all cylinders by a scheduled amount.

Knock sensors contain a piezoelectric material which constantly vibrates and sends an input voltage (signal) to the
PCM while the engine operates. As the intensity of the crystal’s vibration increases, the knock sensor output voltage
also increases.

The voltage signal produced by the knock sensor increases with the amplitude of vibration. The PCM receives the
knock sensor voltage signal as an input. If the signal rises above a predetermined level, the PCM will store that
value in memory and retard ignition timing to reduce engine knock. If the knock sensor voltage exceeds a preset
value, the PCM retards ignition timing for all cylinders. It is not a selective cylinder retard.

The PCM ignores knock sensor input during engine idle conditions. Once the engine speed exceeds a specified
value, knock retard is allowed.

Knock retard uses its own short term and long term memory program.

Long term memory stores previous detonation information in its battery-backed RAM. The maximum authority that
long term memory has over timing retard can be calibrated.

Short term memory is allowed to retard timing up to a preset amount under all operating conditions (as long as rpm
is above the minimum rpm) except at Wide Open Throttle (WOT). The PCM, using short term memory, can respond
quickly to retard timing when engine knock is detected. Short term memory is lost any time the ignition key is turned
off.

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IGNITION CONTROL - SERVICE INFORMATION

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NOTE: Over or under tightening the sensor mounting bolts will affect knock sensor performance, possibly
causing improper spark control. Always use the specified torque when installing the knock sensors.

REMOVAL

3.7L V-6 / 4.7L V-8

The 2 knock sensors (1) are bolted into the cylinder
block under the intake manifold. or.

NOTE: The left sensor is identified by an identifi-
cation tag (LEFT). It is also identified by a larger
bolt head. The Powertrain Control Module (PCM)
must have and know the correct sensor left/right
positions. Do not mix the sensor locations.

1. Disconnect knock sensor dual pigtail harness from

engine wiring harness. This connection is made
near rear of engine.

2. Remove intake manifold. Refer to Engine section.

3. Remove sensor mounting bolts (2) , or. 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.

4. Remove sensors from engine.

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IGNITION CONTROL - SERVICE INFORMATION

DR/DH

5.7L V8

Two sensors are used. Each sensor (1) is bolted into
the outside of cylinder block below the exhaust mani-
fold.

1. Raise vehicle.

2. Disconnect knock sensor electrical connector (5).

3. Remove sensor mounting bolt (2). 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.

4. Remove sensor from engine.

INSTALLATION

3.7L V-6 / 4.7L V-8

NOTE: The left sensor is identified by an identification tag (LEFT). It is also identified by a larger bolt head.
The Powertrain Control Module (PCM) must have and know the correct sensor left/right positions. Do not
mix the sensor locations.

1. Thoroughly clean knock sensor mounting holes.

2. Install sensors into cylinder block.

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 section.

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.

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IGNITION CONTROL - SERVICE INFORMATION

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