If your vehicle is difficult to start or the engine dies after running awhile, it could be a faulty ignition coil. The ignition coil in a vehicle converts low voltage to the high number of volts needed to make a spark in the spark plugs to ignite the fuel. You should be able to replace an ignition coil yourself with no experience. Here are some tips to replace ignition coils.

Prepare to Work

For this project, you need:

  • latex work gloves
  • assorted screwdrivers
  • torque wrench
  • socket wrench
  • tray to hold hardware
  • epoxy
  • dielectric compound
  • replacement wires (optional)
  • auto manual such as Chilton
  • replacement coil

Open the hood to locate the ignition coils. Ignition coils rest on top of spark plugs connected by a wire harness. Ensure it is the ignition coil causing the problem.

Inspect the coil for cracks, which could cause a problem. Apply epoxy as a temporary repair for a crack, if you can't get to replacing it right away. Let the epoxy dry, and test the repair. Also, check for bent or missing wiring, then straighten or replace wires.

Close the hood, idle the vehicle for about half an hour, then tap the module with the screwdriver blade. If the engine stops running, it is good sign of a faulty ignition coil.

Remove the Old Ignition Coil

Take a picture of the battery wiring to help you recall how wires connect. Detach the wires from the battery and the engine to avoid shock. Use a wrench or screwdriver to remove the bolts holding the ignition module in place.

Set the bolts or screws on the tray. Push the locking tab on the wire harness, and disconnect it. Gently rotate the coil, and lift it off the spark plug to remove it.

Install the New Ignition Coil

Add dielectric compound to the boots or bottom of the new ignition coil. Set the new ignition coil in place.

Refer to the auto manual to determine how much torque (force applied to rotate an object) to apply for your vehicle brand. Secure the bolts using the suggested amount of torque with the torque wrench.

Reinstall the battery, ignition module, and reconnect the wiring referring to the photo as a guide. Ensure no wires protrudes from the ignition module.

Test the repair. You don't have to replace the entire ignition module. If you don't trust your skill, or the repair fails, take the vehicle to an auto mechanic, like R N S Service.