TESTING IN PLACE
- Disconnect the coil lead from the center terminal of the distributor cap and hold it about 1 / 2 " from a good ground on the engine.
- Crank the engine. If spark occurs, the problem is probably in the distributor. If there is no spark, the problem is the coil or an upstream component.
On 2.5L engines, the coil is mounted on a bracket and located behind the distributor.
On 3.9L, 5.2L, and 5.9L LDC engines, the coil is mounted to a bracket bolted to the front of the right cylinder head. The bracket is secured to the automatic belt tensioner bracket.
On 5.9L HDC engines, the coil is mounted to a bracket bolted to the air injection pump mounting bracket.
Useful tests can be carried out with an ohmmeter.
- Disconnect the primary wires and the lead to the distributor.
- Check the resistance across the primary wire connectors. It should be about 1 ohm.
- Check the resistance between the one of the primary wire connectors and the high-tension lead. It should be about 12-15 kilo-ohms.
- If resistance is not within spec, replace the coil.
REMOVAL & INSTALLATION
- Disconnect the battery negative terminal.
- Disconnect the primary wires from the coils.
- Disconnect the high-tension lead.
- Remove the securing bolts to remove the coil.
- Installation is the reverse of removal.