🔧 Ascent - Ignition Coil Replacement

Your Ascent uses one ignition coil per cylinder (4 total). Replacing a bad coil restores smooth running and can fix misfires (often felt as shaking, flashing check-engine light, or loss of power).

Difficulty Level: Intermediate | Estimated Time: 1.0-2.0 hours

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⚠️ Safety & Precautions

• 🛑 Let the engine cool fully before starting (turbo and intake parts get very hot).
• 🛑 Disconnect the negative battery terminal before unplugging ignition components.
• 🛑 Don’t pull on wiring—press the connector lock tab and pull the connector body.
• 🛑 Keep dirt out of the spark plug tubes; blow debris away before removing a coil.

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🔧 Required Tools

You'll need the following tools for this repair:

• 10mm socket
• 12mm socket
• 3/8" ratchet
• 3/8" torque wrench (10–80 Nm range)
• 6" socket extension
• Flat-blade screwdriver
• Trim clip removal tool
• Needle-nose pliers
• Flashlight
• Nitrile gloves
• Safety glasses

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🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Ignition coil - Qty: 1 (or Qty: 4 to replace all)
• Dielectric grease (spark plug boot grease) - Qty: 1

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📋 Before You Begin

• Park on level ground, shift to Park, and set the parking brake.
• Open the hood and let the engine cool completely.
• Disconnect the negative battery terminal using a 10mm socket.
• Tip: Take a photo of hoses/connectors first.

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🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Disconnect the battery

• Use a 10mm socket to loosen the negative battery terminal and remove it from the post.
• Move the cable aside so it can’t spring back.

Step 2: Remove the engine cover (if equipped)

• Grip the cover firmly and pull straight upward to release the rubber grommets.
• Use a flashlight to locate the ignition coils on the left and right cylinder heads.

Step 3: If access is tight, remove the top-mounted intake/intercooler ducting

• Use a trim clip removal tool to remove any plastic clips holding the upper duct/shroud.
• Use a flat-blade screwdriver to loosen any hose clamps that block access to the coil area.
• Use needle-nose pliers to slide spring clamps back (if your hoses use spring clamps).
• Tip: Cover openings with a clean rag.

Step 4: Unplug the ignition coil connector

• Press the lock tab on the coil’s electrical connector and pull the connector straight off.
• If the tab is stubborn, use a flat-blade screwdriver gently to help depress it (don’t pry hard).

Step 5: Remove the ignition coil

• Use a 10mm socket with a 6" socket extension and 3/8" ratchet to remove the coil hold-down bolt.
• Twist the coil slightly, then pull it straight up to remove it from the spark plug tube.
• Use a flashlight to check the spark plug tube for oil or water. If you see oil, stop and address the leak before continuing.

Step 6: Install the new ignition coil

• Apply a small dab of dielectric grease inside the rubber boot (this grease helps prevent moisture and makes removal easier later).
• Push the new coil straight down until it fully seats on the spark plug.
• Install the hold-down bolt by hand first to avoid cross-threading.
• Tighten the bolt using a 3/8" torque wrench to Torque to 7.5 Nm (66 in-lbs). (A torque wrench measures tightening force so you don’t overtighten.)

Step 7: Reconnect the coil connector

• Push the electrical connector on until it clicks.
• Gently tug the connector to confirm it’s locked.

Step 8: Repeat for any other coils you’re replacing

• Replace coils one at a time so connectors don’t get mixed up.
• If you’re replacing all four, repeat Steps 4–7 for each coil.

Step 9: Reinstall ducting/cover and reconnect the battery

• Reinstall any ducting you removed using the trim clip removal tool, flat-blade screwdriver, 10mm socket, and 12mm socket as needed.
• Reinstall the engine cover by aligning it and pressing down firmly.
• Reconnect the negative battery terminal using a 10mm socket and tighten securely.

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✅ After Repair

• Start the engine and let it idle for 1–2 minutes. It should run smooth with no misfire.
• If the check-engine light was on, it may take a few drive cycles to clear on its own, or you can clear codes with a scan tool.
• Test drive gently for 10–15 minutes and recheck for any loose clamps/odd noises from the intake area.

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💰 DIY vs Shop Cost

Shop Cost: $250-$650 (parts + labor)

DIY Cost: $60-$400 (parts only, depending on 1 coil vs all 4)

You Save: $150-$350 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 1.0-2.0 hours.

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🎯 Ready to get started?

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