Chrysler Front Wheel Drive Cars 6-CYL 1988-1995 Repair Information

Ignition Coil

Print

TESTING



Except Premier and Monaco

See Figure 1

The ignition coil is designed to operate without an external ballast resistor. Inspect the coil for arcing. Test the coil primary and secondary resistance.

To measure the primary resistance, connect an ohmmeter between the positive (+) and negative (-) terminals (the terminals which are connected to the engine wiring harness) on the coil. To test the secondary resistance, connect an ohmmeter between the positive (+) coil terminal and the high voltage cable terminal on the coil. Then, measure the resistance between the positive (+) coil terminal and the coil case; the resistance for the case should exhibit infinite resistance. For coils manufactured by Diamond, the primary resistance at 70-80°F (21-27°C) should be 0.97-1.18 ohms and the secondary resistance should be 11,300-15,300 ohms. Coils built by the Toyodenso company should exhibit a primary resistance at 70-80°F (21-27°C) of 0.95-1.20 ohms and a secondary resistance of 11,300-13,300 ohms. Replace any coil with a new one if it does not meet the specifications.



Click image to see an enlarged view

Fig. Fig. 1: Ignition coil cables and terminal configuration-except Premier and Monaco

If the ignition coil is replaced with a new one due to a burned tower, carbon tracking, arcing at the tower, or damage to the terminal or boot on the coil end of the secondary cable, the cable must also be replaced with a new one. Arcing at the tower will carbonize the nipple which, if it is connected to a new coil, will cause the coil to fail.

If a secondary cable shows any signs of damage, the cable should be replaced with a new cable and new terminal. Carbon tracking on the old cable can cause arcing and the failure of a new coil.

TESTING FOR SPARK AT COIL

See Figure 2


WARNING
Spark plug cables may be damaged if this test is performed with more than1/4inch (6mm) clearance between the cable and an engine ground.

Remove the coil secondary cable from the distributor cap. Hold the end of the cable about 1 / 4 inch (6mm) away from a good engine ground. Crank the engine and inspect for spark at the coil secondary cable.

There must be a constant spark at the coil secondary cable. If the spark is constant, have a helper continue to crank the engine and, while slowly moving the coil secondary cable away from the ground, look for arcing at the coil tower. If arcing occurs at the tower, replace the coil with a new one. If the spark is not constant or there is no spark, proceed to the failure-to-start test.



Click image to see an enlarged view

Fig. Fig. 2: Checking for spark at the ignition coil-except Premier and Monaco

If a constant spark is present and no arcing occurs at the coil tower, the ignition system is producing the necessary high secondary voltage. However, make sure that the spark plugs are firing. Inspect the distributor rotor, cap, spark plug cables, and spark plugs-refer to General Information & Maintenance . If they are in proper working order, the ignition system is not the reason why the engine will not start. Inspect the fuel system and engine for proper operation.

Premier and Monaco

The ignition coil is designed to operate without an external ballast resistor. Inspect the coil for arcing. Test the coil primary and secondary resistance.

To measure the primary resistance, connect an ohmmeter between the positive (+) and negative (-) terminals (the terminals which are connected to the engine wiring harness) on the coil. To test the secondary resistance, connect an ohmmeter between the positive (+) coil terminal and the high voltage cable terminal on the coil. Then, measure the resistance between the positive (+) coil terminal and the coil case; the resistance for the case should exhibit infinite resistance. The primary resistance at 70-80°F (21-27°C) should be 0.5-1.0 ohms and the secondary resistance should be 4,500-5,000 ohms. Replace any coil with a new one if it does not meet the specifications.

If the ignition coil is replaced with a new one due to a burned tower, carbon tracking, arcing at the tower, or damage to the terminal or boot on the coil end of the secondary cable, the cable must also be replaced with a new one. Arcing at the tower will carbonize the nipple which, if it is connected to a new coil, will cause the coil to fail.

If a secondary cable shows any signs of damage, the cable should be replaced with a new cable and new terminal. Carbon tracking on the old cable can cause arcing and the failure of a new coil.

TESTING FOR SPARK AT COIL

WARNING
Spark plug cables may be damaged if this test is performed with more than1/4inch (6mm) clearance between the cable and an engine ground.

Remove the coil secondary cable from the distributor cap. Hold the end of the cable about 1 / 4 inch (6mm) away from a good engine ground. Crank the engine and inspect for spark at the coil secondary cable.

There must be a constant spark at the coil secondary cable. If the spark is constant, have a helper continue to crank the engine and, while slowly moving the coil secondary cable away from the ground, look for arcing at the coil tower. If arcing occurs at the tower, replace the coil with a new one.

If a constant spark is present and no arcing occurs at the coil tower, the ignition system is producing the necessary high secondary voltage. However, make sure that the spark plugs are firing. Inspect the distributor rotor, cap, spark plug cables, and spark plugs-refer to General Information & Maintenance . If they are in proper working order, the ignition system is not the reason why the engine will not start. Inspect the fuel system and engine for proper operation.

REMOVAL & INSTALLATION



Except Premier and Monaco

See Figures 3 through 8

The ignition coil is located on the firewall side of the intake manifold.

  1. Remove the air cleaner assembly from the engine.
  2.  
  3. Disconnect the negative (-) battery cable from the battery.
  4.  
  5. Disconnect the ignition cable from the coil.
  6.  
  7. Unplug the wiring harness connector from the coil.
  8.  
  9. Loosen and remove the coil mounting screws, then remove the coil from the vehicle.
  10.  



Click image to see an enlarged view

Fig. Fig. 3: Ignition coil mounting position-except Premier and Monaco



Click image to see an enlarged view

Fig. Fig. 4: Unplug and label the engine wiring harness connector from the ignition coil ...



Click image to see an enlarged view

Fig. Fig. 5: ... then disconnect the coil-to-distributor high tension cable



Click image to see an enlarged view

Fig. Fig. 6: Loosen and remove the top mounting bolt from the intake manifold and ignition coil bracket



Click image to see an enlarged view

Fig. Fig. 7: After removing the air cleaner housing box, remove the 2 lower ignition coil mounting bolts ...



Click image to see an enlarged view

Fig. Fig. 8: ... then remove the ignition coil and mounting bracket together from the engine

To install:
  1. Loosely install the ignition coil onto the intake manifold. Tighten the intake manifold fastener to 10 ft. lbs. (13 Nm) of torque. Tighten the ignition coil bracket fasteners to 7 ft. lbs. (10 Nm) of torque.
  2.  
  3. Attach the wiring harness connector to the coil.
  4.  
  5. Connect the distributor ignition cable to the coil.
  6.  
  7. Install the air cleaner assembly. Tighten the air cleaner fasteners to 18 ft. lbs. (25 Nm) of torque.
  8.  
  9. Connect the negative battery cable to the battery.
  10.  

Premier and Monaco

See Figure 9

  1. Disconnect the negative (-) battery cable from the battery.
  2.  
  3. Unplug the Ignition Control Module (ICM)/coil electrical connectors from the coil.
  4.  
  5. Disconnect the high tension wire from the coil.
  6.  
  7. Loosen and remove the coil mounting nuts, then remove the ICM/coil from its mounting position.
  8.  



Click image to see an enlarged view

Fig. Fig. 9: Ignition Control Module (ICM)/ ignition coil assembly and related components-Premier and Monaco

To install:
  1. Position the ICM/coil in place and secure with the mounting nuts.
  2.  
  3. Snap the electrical connectors into place on the ICM/coil.
  4.  
  5. Snap the high tension wire onto the ICM/coil.
  6.  
  7. Connect the negative (-) battery cable to the battery.
  8.  

 
label.common.footer.alt.autozoneLogo