Ram 1500, 2500, 3500, 2WD and 4WD, 2001-2005

Ignition Coil

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Removal & Installation



3.7L Engine

An individual ignition coil is used for each spark plug. The coil fits into machined holes in the cylinder head. A mounting stud/nut secures each coil to the top of the intake manifold. 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. These rubber boots and springs are a permanent part of the coil and are not serviced separately. An O-ring is used to seal the coil at the opening into the cylinder head.


NOTE
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.

  1. Disconnect electrical connector from coil by pushing downward on release lock on top of connector and pull connector from coil.
  2.  
  3. Clean area at base of coil with compressed air before removal.
  4.  
  5. Remove coil mounting nut from mounting stud.
  6.  
  7. Carefully pull up coil from cylinder head opening with a slight twisting action.
  8.  
  9. Remove coil from vehicle.

    Click image to see an enlarged view

    Fig. View of the ignition coil (2), O-ring (2) and electrical connector (3)-3.7L engine

    View of the ignition coil (2), O-ring (2) and electrical connector (3)-3.7L engine
  10.  

To install:

  1. Using compressed air, blow out any dirt or contaminants from around top of spark plug.
  2.  
  3. Check condition of coil O-ring and replace as necessary. To aid in coil installation, apply silicone to coil O-ring.
  4.  
  5. Position ignition coil into cylinder head opening and push onto spark plug. Do this while guiding coil base over mounting stud.
  6.  
  7. Install coil mounting stud nut and tighten to 80 inch lbs. (7 Nm)
  8.  
  9. Connect electrical connector to coil by snapping into position.
  10.  
  11. If necessary, install throttle body air tube.
  12.  

4.7L Engine

An individual ignition coil is used for each spark plug. The coil fits into machined holes in the cylinder head. A mounting stud/nut secures each coil to the top of the intake manifold. 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. These rubber boots and springs are a permanent part of the coil and are not serviced separately. An O-ring is used to seal the coil at the opening into the cylinder head.


NOTE
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.

  1. Disconnect electrical connector from coil by pushing downward on release lock on top of connector and pull connector from coil.
  2.  
  3. Clean area at base of coil with compressed air before removal.
  4.  
  5. Remove coil mounting nut from mounting stud.
  6.  
  7. Carefully pull up coil from cylinder head opening with a slight twisting action.
  8.  
  9. Remove the coil from vehicle.

    Click image to see an enlarged view

    Fig. Location of the ignition coil (1), electrical connector (2) and coil mounting stud/nut (3)-4.7L engine

    Location of the ignition coil (1), electrical connector (2) and coil mounting stud/nut (3)-4.7L engine
  10.  

To install:

  1. Using compressed air, blow out any dirt or contaminants from around top of spark plug.
  2.  
  3. Check condition of coil O-ring and replace as necessary. To aid in coil installation, apply silicone to coil O-ring.
  4.  
  5. Position ignition coil into cylinder head opening and push onto spark plug. Do this while guiding coil base over mounting stud.
  6.  
  7. Install coil mounting stud nut and tighten to 80 inch lbs. (7 Nm).
  8.  
  9. Connect electrical connector to coil by snapping into position.
  10.  
  11. If necessary, install throttle body air tube.
  12.  

5.7L Engine

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 position.

An individual ignition coil is used at each cylinder. The coil mounts to the top of the valve cover with 2 bolts. 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.


NOTE
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.



Click image to see an enlarged view

Fig. View of the slide lock (1), spark plug cable (2), release lock/tab (3), electrical connector (4), ignition coil

View of the slide lock (1), spark plug cable (2), release lock/tab (3), electrical connector (4), ignition coil
  1. Unlock electrical connector by moving slide lock first (1). Press on release lock (3) while pulling electrical connector from coil.
  2.  
  3. Disconnect secondary high-voltage cable (2) from coil with a twisting action.
  4.  
  5. Clean area at base of coil with compressed air before removal.
  6.  
  7. Remove two mounting bolts (6) (note that mounting bolts are retained to coil).
  8.  
  9. Carefully pull up coil from cylinder head opening with a slight twisting action.
  10.  
  11. Remove coil from vehicle.
    NOTE
    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.

  12.  

To install:

  1. Using compressed air, blow out any dirt or contaminants from around top of spark plug.
  2.  
  3. 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.
  4.  
  5. Position ignition coil into cylinder head opening and push onto spark plug. Twist coil into position.
  6.  
  7. Install 2 coil mounting bolts and torque to 9 ft. lbs. (12 Nm).
  8.  
  9. Connect electrical connector to coil by snapping into position.
  10.  
  11. Install cable to coil. To prevent ignition crossfire, spark plug cables MUST be placed in cable tray (routing loom) into their original position.
  12.  
  13. If necessary, install throttle body air tube.
  14.  

8.0L Engine

Two separate coil packs containing a total of five independent coils are attached to a common mounting bracket located above the right engine valve cover. The front and rear coil packs can be serviced separately.

  1. Remove the secondary spark plug cables from the coil packs. Note position of cables before removal.
  2.  
  3. Disconnect the primary wiring harness connectors at coil packs.
  4.  
  5. Remove the four (4) coil pack-to-coil mounting bracket bolts for the coil pack being serviced.
  6.  
  7. Remove coil(s) from mounting bracket.

    Click image to see an enlarged view

    Fig. View of the ignition coil packs-8.0L engine

    View of the ignition coil packs-8.0L engine
  8.  

To install:

  1. Position coil packs to mounting bracket (primary wiring connectors face downward).
  2.  
  3. Install coil pack mounting bolts. Tighten bolts to 89 inch lbs. (10 Nm).
  4.  
  5. Install coil pack-to-engine mounting bracket (if necessary).
  6.  
  7. Connect primary wiring connectors to coil packs (four wire connector to front coil pack and three wire connector to rear coil pack).
  8.  
  9. Connect secondary spark plug cables to coil packs. Refer to the accompanying illustration for correct cable order

    Click image to see an enlarged view

    Fig. Spark plug cable routing and firing order-8.0L engine

    Spark plug cable routing and firing order-8.0L engine
  10.  

Testing



8.0L Engine

Coil packs are mounted above the right engine valve cover.

  1. Disconnect the negative battery cable.
  2.  
  3. Mark and disconnect the spark plug leads at the coil packs. Disconnect the primary wiring at the connectors.
  4.  
  5. Check resistance across each pair of spark plug (high tension) terminals: 3/2, 7/4, 1/6, 9/8, 5/10. Resistance should be 11-15K ohms.
  6.  
  7. Check resistance across the (low tension) primary windings by connecting the ohmmeter between the B+ terminal and each of the coil terminals in turn. In each case, resistance should be 0.53-0.65 ohms.
  8.  
  9. If resistance is not within specification, the coil pack will have to be replaced.

    Click image to see an enlarged view

    Fig. Ignition coil packs-V-10

    Ignition coil packs-V-10

    Click image to see an enlarged view

    Fig. Checking high tension (secondary) circuit resistance-6-pack shown

    Checking high tension (secondary) circuit resistance-6-pack shown

    Click image to see an enlarged view

    Fig. Checking primary winding (low tension) circuit resistance: one probe to "B+" and the other to "Left", "Right" and "Center" terminals in turn-6-pack shown

    Checking primary winding (low tension) circuit resistance: one probe to "B+" and the other to "Left", "Right" and "Center" terminals in turn-6-pack shown

    Click image to see an enlarged view

    Fig. Checking primary winding (low tension) circuit resistance: one probe to "B+" and the other to "Left" and "Right" terminals in turn-4-pack shown

    Checking primary winding (low tension) circuit resistance: one probe to "B+" and the other to "Left" and "Right" terminals in turn-4-pack shown
  10.  

Except 8.0L Engine

The coil(s) can be checked with an ohmmeter.

  1. Disconnect the negative battery cable.
  2.  
  3. Remove the coil from the engine.
  4.  
  5. Primary winding resistance (across the low tension terminals) should be 0.6-0.9 ohms.
  6.  
  7. Secondary winding resistance (across the spark plug lead and one of the low tension terminals) should be 6-9K ohms.
  8.  
  9. Replace any coil not within specification.
  10.  

 
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