🔧 Civic - Ignition Coil Replacement

Your Civic uses coil-on-plug ignition coils (one coil per cylinder) mounted on top of the engine. Replacing a weak or failed coil can fix misfires, rough idle, and flashing check-engine lights.

Difficulty Level: Beginner | Estimated Time: 0.5-1.0 hours

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⚠️ Safety & Precautions

• ⚠️ Work on a cool engine to avoid burns.
• ⚠️ Disconnect the negative battery cable to prevent accidental shorts.
• ⚠️ Do not pull on wiring—release connector locks first.
• ⚠️ If the check-engine light is flashing, avoid driving until repaired (can damage the catalytic converter).

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🔧 Required Tools

You'll need the following tools for this repair:

• 10mm socket
• 1/4" drive ratchet
• 6" socket extension
• Torque wrench (5-25 Nm range)
• Flathead screwdriver
• Needle-nose pliers
• Small pick tool
• Dielectric grease
• Nitrile gloves
• Safety glasses

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🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Ignition coil - Qty: 4 Best practice: replace as a set
• Dielectric grease - Qty: 1

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📋 Before You Begin

• 🅿️ Park on level ground, put the shifter in neutral, and set the parking brake.
• 🔋 Use a 10mm socket to disconnect the negative battery cable and move it aside.
• 🧼 If dirt is sitting around the coils, wipe/blow it away so it doesn’t fall into the spark plug wells.

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🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Locate the ignition coils

• Open the hood and look at the top/front of the engine valve cover.
• You’ll see 4 ignition coils in a row, each held down by a single 10mm bolt.

Step 2: Unplug the electrical connectors

• Use a small pick tool to gently lift the connector lock tab if it’s stuck (do not pry hard).
• Press the release on the connector and pull it straight off the coil.
• If it won’t budge, wiggle—don’t yank.

Step 3: Remove the coil hold-down bolts

• Use a 10mm socket, 6" extension, and ratchet to remove the 10mm bolt from each coil.
• Set the bolts aside where they won’t drop into the engine bay.

Step 4: Remove the ignition coils

• Grip the coil body and twist it slightly left-right to break it free.
• Pull the coil straight up and out of the spark plug well.
• Coil-on-plug means the coil sits over the spark plug.

Step 5: Prep and install the new coils

• Put a small smear of dielectric grease inside the new coil boot (the rubber tip). Dielectric grease helps seal out moisture and makes future removal easier.
• Insert the new coil straight down into the spark plug well until it fully seats.

Step 6: Reinstall and torque the hold-down bolts

• Start each bolt by hand first to avoid cross-threading.
• Use a torque wrench with a 10mm socket to tighten each bolt: Torque to 12 Nm (9 ft-lbs).

Step 7: Reconnect the electrical connectors

• Push each connector onto its coil until it clicks/locks.
• Gently tug to confirm it’s fully latched.

Step 8: Reconnect the battery

• Use a 10mm socket to reconnect the negative battery cable.
• Snug it firmly (do not overtighten and strip the terminal).

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✅ After Repair

• 🔎 Start the engine and let it idle for 1-2 minutes. It should run smooth with no shaking.
• 🚗 Take a short test drive and confirm power feels normal.
• 🛠️ If the check-engine light stays on, the code may need to be cleared, or a spark plug/fuel issue may still be present.
• 👃 If you smell raw fuel or the engine runs worse, shut it off and re-check coil connectors (a loose connector is common).

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💰 DIY vs Shop Cost

Shop Cost: $250-$600 (parts + labor)

DIY Cost: $120-$400 (parts only)

You Save: $130-$200 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 0.5-1.0 hours.

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🎯 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.