Is y our Kia Optima engine misfiring, has a rough idle, and the check engine light is on due to a faulty spark plug and ignition coil? Learn how to fix the problem by replacing your vehicle’s spark plugs and ignition coils. This guide is a step-by-step instruction on replacing the coil pack and spark plug on a 2016-2020 Kia Optima.
What you will need
- Ignition coil
- Spark plugs (FXU16HR11) – The OEM spark plugs are laser iridium spark plugs. Possible part numbers include NGK SILZKR7E11, SILZKR7E-11 or SILZKR7E 11 or 92315.
- 10mm socket wrench
- 5/8 spark plug socket
- Ratchet extension
- Torque Wrench
- YOUCANIC Scanner
- Open the hood. Pull the hood release under the dashboard. Unlock the hood latch and pull the hood up.
- Remove the engine cover by pulling it up.
- Disconnect the electrical connectors on each ignition coil. Pull out the locking clip and then pull the connector out while squeezing the clip.
- Remove the size ten bolts on each ignition coil using a socket wrench. Remove the coil pack by pulling them up.
- Check for any burn marks or cracks on the ignition coil; you can also check what ignition coil is misfiring using an OBD-II scanner.
- Loosen and remove the spark plug using a 5/8 spark plug socket with a ratchet extension.
- Put the new spark plug into the spark plug socket and carefully lower them into the engine. Do not allow the spark plugs to drop into the engine block, as that can lead to damage at the spark plug’s tip. Then tighten the spark plug to the proper torque specification. Recommend torque is 15ft/lbs.
- Line up the new ignition coil and push them in.
- Reinstall the 10mm bolts on each ignition coil.
- Connect the electrical connectors back to the ignition coil. Push the connectors until they lock-in.
- Line up the engine cover and push it to lock the rubber grommets.
- Spark Plug: 10.8 to 18.0 lb-ft of torque (14.7 to 24.5 Nm)
Spark Plug Gap
- Gapped to 0.044
Check Engine Light On
If the check engine light is still on after replacing your vehicle’s spark plugs and ignition coils, you can use the YOUCANIC Full System Scanner to clear the stored codes. This scanner can read and clear fault codes through every vehicle’s control module.
We hope you find the 2016-2020 Kia Optima Spark Plugs & Ignition Coils Replacement guide helpful. Check these troubleshooting and repair guides for more help on your Kia.
Have questions about your car? Get assistance in our newly launched forum section. We’re here to provide support!