Safety First:
* Disconnect the negative battery terminal before starting any work on the ignition system. This prevents accidental shocks and damage to electronic components.
* Wear safety glasses to protect your eyes from debris.
* Work in a well-ventilated area.
Tools You'll Need:
* Socket wrench set (likely 10mm, 7/16", and possibly others)
* Ratchet
* Extension(s) for your ratchet
* Possibly a spark plug socket (depending on coil design)
* Pen or marker (to label coils if necessary)
* Gloves (optional, but recommended)
* New ignition coils (ensure you purchase the correct ones for your year and engine)
General Steps:
1. Locate the Ignition Coils: They're usually located on top of the engine, one per cylinder. They often look like small, black rectangular boxes. Consult your repair manual for the exact location on your specific Expedition model.
2. Disconnect the Coil Pack: Each coil usually has a single electrical connector. Carefully disconnect this connector. Some connectors may have a clip or locking mechanism; you may need to gently pry it open.
3. Remove the Coil(s): This is where the process can vary.
* Some Expedition models have coils that are simply clipped into place: Gently pry the coil up and off the spark plug. Be careful not to damage the coil or spark plug.
* Others may use bolts: You might need to remove a bolt or two securing each coil to the valve cover.
4. Inspect the Spark Plugs (Optional but Recommended): While you have the coils off, it's a good opportunity to visually inspect the spark plugs for wear and tear. If they look worn, consider replacing them at the same time (this often extends the life of your coils too).
5. Install the New Coils: Follow the reverse procedure of removal. Ensure the new coils are seated correctly and securely fastened.
6. Reconnect the Electrical Connectors: Carefully reattach the electrical connectors to the new coils.
7. Reconnect the Battery: Reconnect the negative battery terminal.
8. Start the Engine: Start the engine and listen for any unusual sounds or misfires. If everything is working correctly, the engine should run smoothly.
Important Considerations:
* Coil Pack vs. Individual Coils: Some Expeditions have individual coils for each spark plug, while others have coil packs that cover multiple cylinders. The procedure will vary slightly depending on this design.
* Year and Engine: The specific steps and tools may vary depending on the year and engine type of your Ford Expedition. Always refer to your vehicle's repair manual for model-specific instructions.
* Misfire Codes: If you're replacing coils due to a misfire, you might want to use an OBD-II scanner to check for any remaining trouble codes after the replacement.
If you're not comfortable performing this repair yourself, it's best to take your vehicle to a qualified mechanic. Improperly installed ignition coils can damage other engine components.
