How to Replace Ignition Coils on a 2018 Kia Sportage (Fix Misfires & Rough Idle)
Step-by-step coil swap with required tools/parts, safety tips, and the correct 9.8 Nm (87 in-lb) torque spec for 2017, 2018, 2019, 2020, 2021, 2022
How to Replace Ignition Coils on a 2018 Kia Sportage (Fix Misfires & Rough Idle)
Step-by-step coil swap with required tools/parts, safety tips, and the correct 9.8 Nm (87 in-lb) torque spec for 2017, 2018, 2019, 2020, 2021, 2022
🔧 Sportage - Ignition Coil Replacement
Your Sportage uses one ignition coil per cylinder. Replacing a bad coil can fix misfires, rough idle, and flashing check engine lights because each coil makes the spark plug fire.
Difficulty Level: Beginner | Estimated Time: 0.5-1.5 hours
⚠️ Safety & Precautions
- ⚠️ Work on a fully cool engine; coils sit on a hot valve cover.
- ⚠️ Disconnect the negative battery cable to prevent accidental shorts.
- ⚠️ Don’t pull on wiring; release electrical connector locks first.
- ⚠️ If the check engine light is flashing, avoid driving until repaired (can damage the catalytic converter).
🔧 Required Tools
You'll need the following tools for this repair:
- 10mm socket
- 1/4" drive ratchet
- 6" extension (1/4" drive)
- Torque wrench (in-lb or low Nm range)
- Trim clip remover
- Small flathead screwdriver
- Needle-nose pliers
- Shop towels
- Nitrile gloves
- Safety glasses
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Ignition coil - Qty: 1-4 Replace only failed, or all four.
- Dielectric grease - Qty: 1
📋 Before You Begin
- Park on level ground, shift to Park, and set the parking brake.
- Open the hood and let the engine cool completely.
- Use a 10mm socket to disconnect the negative battery terminal and tuck it aside so it can’t spring back.
- If you’re replacing only one coil, note which cylinder was misfiring (P0301-P0304) before disconnecting the battery.
🔨 Step-by-Step Instructions
Follow these steps in order:
Step 1: Remove the engine cover (if equipped)
- Lift the cover straight up by hand; if it uses grommets it will pop off.
- If any plastic clips are present, remove them with a trim clip remover.
Step 2: Locate the ignition coils
- The coils sit on top of the valve cover, one per cylinder, with an electrical connector on each.
- Take a quick photo for reference.
Step 3: Unplug the coil electrical connector
- Press the connector lock tab by hand; if it’s stubborn, gently help the tab with a small flathead screwdriver.
- Pull the connector straight off (don’t yank the wires).
- Wiggle the plug, don’t force it.
Step 4: Remove the coil hold-down bolt
- Use a 10mm socket, 6" extension, and 1/4" ratchet to remove the single bolt holding the coil down.
- Set the bolt aside where it won’t fall into the engine bay.
Step 5: Pull the ignition coil out
- Twist the coil slightly left-right, then pull straight up to remove it from the spark plug tube.
- If it feels stuck, keep twisting gently—don’t pry on the valve cover.
Step 6: Prep the new coil
- Apply a tiny smear of dielectric grease inside the rubber boot (this helps seal and eases future removal).
- Wipe any dirt off the spark plug tube area with shop towels before reinstalling.
Step 7: Install the new coil
- Push the coil straight down until you feel it fully seat on the spark plug.
- Reinstall the hold-down bolt using a 10mm socket.
- Tighten with a torque wrench: Torque to 9.8 Nm (87 in-lbs).
Step 8: Reconnect the electrical connector
- Push the connector on until it clicks/locks into place.
- Gently tug-check it by hand to confirm it’s latched.
Step 9: Repeat for other coils (if replacing more than one)
- Repeat Steps 3-8 for each additional cylinder.
- Replace coils one at a time to avoid mix-ups.
Step 10: Reinstall the engine cover and reconnect the battery
- Reinstall the engine cover by pressing it down into the grommets (or reinstall clips with needle-nose pliers if equipped).
- Reconnect the negative battery cable using a 10mm socket.
✅ After Repair
- Start the engine and let it idle for 1-2 minutes; it should run smooth with no shaking.
- If the check engine light stays on, the code may need clearing with a scan tool, or there may be another issue (spark plug, injector, vacuum leak).
- Take a 10-minute test drive and recheck for any warning lights or hesitation under acceleration.
- If you had a flashing check engine light before, confirm it does not return under load.
💰 DIY vs Shop Cost
Shop Cost: $250-$700 (parts + labor)
DIY Cost: $60-$400 (parts only)
You Save: $190-$300+ by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 0.7-1.2 hours.
🎯 Ready to get started?
HowToo makes it easy: same-day/2-day shipping on every part, plus all the tools and specialty tools you need! Check out the parts and tools sections below to add everything to your cart.


















