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How to Replace a Coil Pack

by Dan Ferrell

A faulty spark on the ignition system of your car may be tracked down to an ignition coil. When this happens, the engine misses, stalls or even refuses to start. Weaken windings inside a coil eventually break, creating resistance for the spark going through them. Unfortunately, you cannot replace the windings, but you can replace the faulty coil, or coil pack.

Remove the Coil Pack

Disconnect the ground battery cable using a wrench.

Open the hood and locate the coil pack near the engine of your car. The easiest way is to follow any of the spark plug wires. One end of the wire is connected to the spark plug; the other plugs into the coil pack. The coil may be to the left of the engine compartment, or to the backside of the engine.

Remove the air cleaner assembly from the top of the engine to gain access to the coil pack, if necessary. Use a wrench or standard screwdriver.

Raise the front of your vehicle using a floor jack, and support it on 2 jack stands, if the coil pack on your car is on the backside of the engine. You will need to work from underneath the vehicle to remove it.

Unplug the wiring harness from the coil pack by pressing the lock tab on the plastic connector and pulling the connector off the coil assembly fitting.

Label the spark plug wires before you disconnect them from the coil pack, if necessary. The wires have to be reinstalled at the correct place for proper engine operation.

Unplug the spark plug wires from the coil pack by twisting and pulling the wires from the rubber boot. On other models, squeeze the locking tabs to release the wire from the coil boot retainers.

Unscrew the bolts holding the coil pack assembly to the mounting bracket, using a ratchet and socket.

Lift the coil pack assembly from the engine.

Install the New Coil Pack

Set the new coil pack in place, and start the mounting bolts by hand to avoid thread damage.

Tighten the mounting bolts, using the ratchet and socket.

Apply dielectric grease to the wire connector inside the spark-plug wire boots, using a standard screwdriver.

Plug the spark plug wires on the coil pack assembly, making sure you plug them on the correct coil towers.

Plug the wiring harness on the coil pack assembly.

Lower the vehicle if you had to raise it.

Install the air cleaner assembly, using the wrench or standard screwdriver, if you had to remove it.

Connect the ground battery cable, using the wrench.

Items you will need


About the Author

Since 2003 Dan Ferrell has contributed general and consumer-oriented news to television and the Web. His work has appeared in Texas, New Mexico and Miami and on various websites. Ferrell is a certified automation and control technician from the Advanced Technology Center in El Paso, Texas.

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Photo Credits

  • Photo courtesy of Aidan Wojtas at