Q: How Do You Remove and Install a Ignition Coil on Dodge Grand Caravan?
A: To remove a conventional coil, start by detaching the cable from the negative battery terminal. Then, mark the wires and terminals with numbered tape and remove the primary wires and high-tension cable from the coil. If it's a four-cylinder engine, disconnect the primary electrical connector and high-tension cable, and remove the mounting bolts. For an earlier type coil on the fenderwell, disconnect the primary wires and high-tension cable, and remove the mounting bracket bolts. If the coil is bad, loosen the clamp pinch screw and transfer the clamp/mounting bracket to the new coil. Make sure to release the locking tab on the electrical connector for the primary wires on the later type engine-mounted coil before disconnecting it. On 3.0L engines, remove the mounting bolts from the intake plenum and intake manifold. Disconnect the coil mounting bracket, remove the coil/bracket assembly, clean the outer case, and check for cracks or damage. Clean the coil primary terminals and check the coil tower terminal for corrosion, using a wire brush if necessary. Check the coil primary resistance by attaching the leads of an ohmmeter to the positive and negative terminals. Check the coil secondary resistance by hooking one ohmmeter lead to a primary terminal and the other lead to the large center (high-tension) terminal. If the measured resistances are not as specified, the coil is likely defective and should be replaced. To install the coil, hook up the wires and attach the cable to the negative battery terminal. For a Direct Ignition System (DIS) coil pack on 3.3L and 3.8L engines, start by labeling the six spark plug wires and measuring the resistance of each cable. It should be 3 to 12 k-ohms per foot of cable, replacing any cable not within this range. Remove the four coil pack mounting bolts, lift up the coil pack, and unplug the electrical connector. Measure the resistance on the primary side of each coil with a digital ohmmeter, making sure the test lead probes have good contact with the terminals. Connect an ohmmeter between the B+ pin and the pin corresponding to the particular cylinder at the coil. Measure the secondary resistance of the coil between the paired high tension towers of each group of cylinders. If any coil in the coil pack fails either of the above tests, replace the coil pack. Installation is the reverse of removal.