The ignition module on the 2.5L and non-HVS 4.3L engine is located inside the distributor; it may be replaced without removing the distributor from the engine. The ignition control module (ICM) on 1995 and later VIN W 4.3L engines is just an electronic switch and does no controlling of the ignition system. It is attached to the ignition coil bracket.1985-94 (non-HVS) Engines
See Figures 1, 2, 3 and 4
- Disconnect the negative battery terminal and remove the console cover.
- Remove the distributor cap and the rotor.
- If the flange, of the distributor shaft is positioned above the module, place a socket on the crankshaft pulley bolt and rotate the crankshaft (turning the distributor shaft) to provide clearance to the ignition module.
- Remove the ignition module-to-distributor bolts, lift the module and disconnect the electrical connectors from it.
- If the module is suspected as being defective, take it to a module testing machine and have it tested.
When replacing the module, be sure to coat the module-to-distributor surface with silicone lubricant (dielectric compound) that will provide heat dissipation.To install:
- Apply silicone heat sink compound to the module mounting area of the distributor. Install the rotor, the distributor cap and connect the negative battery cable.
1995-96 (HVS) Engines
- Disconnect the negative battery terminal and remove the console cover inside the vehicle.
- Disconnect the engine control switch and tachometer terminals from the ignition coil and module.
- Disconnect the ignition coil-to-distributor lead wire from the coil.
- Remove the coil bracket/module assembly-to-engine bracket nuts and lift the assembly from the engine.
If necessary to remove the module from the bracket, perform the following procedures:
- Using a drill, drill out the module-to-bracket rivets.
- Using a center punch, drive the rivets from the module-to-bracket assembly.
- Remove the module from the coil bracket.
- Install the module on the bracket with two screws, position the coil on the engine and torque the nuts to 20 ft. lbs. (27 Nm).
- Connect the coil connectors and negative battery cable. Install the console cover.