🔧 Traverse - Ignition Coil Replacement

Your Traverse uses one ignition coil per cylinder (6 total). Replacing a bad coil can fix misfires, rough running, and flashing check-engine lights, and replacing coils in sets can prevent repeat failures.

Difficulty Level: Intermediate | Estimated Time: 1.0-2.5 hours

---

⚠️ Safety & Precautions

• ⚠️ Let the engine cool fully; coils sit near hot parts.
• ⚠️ Disconnect the negative battery cable before unplugging ignition components.
• ⚠️ If you remove the upper intake, keep bolts and parts organized to avoid vacuum leaks.
• ⚠️ Do not pull on wires; always release connector locks first.

---

🔧 Required Tools

You'll need the following tools for this repair:

• 10mm socket
• 8mm socket
• 1/4" drive ratchet
• 3/8" drive ratchet
• 3" extension (1/4" drive)
• 6" extension (3/8" drive)
• Torque wrench (inch-pound)
• Torque wrench (foot-pound)
• Flat-blade screwdriver
• Trim clip removal tool
• Pick tool
• Shop light
• Painter’s tape
• Marker
• Nitrile gloves
• Safety glasses

---

🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Ignition coil - Qty: 1-6
• Upper intake manifold gasket set - Qty: 1 (needed if rear-bank coils are replaced)
• Dielectric grease - Qty: 1 (optional)

---

📋 Before You Begin

• Park on level ground, shift to Park, and set the parking brake.
• Open the hood and remove any loose items from the cowl area.
• Disconnect the negative battery cable using a 10mm socket.
• Use painter’s tape and a marker to label hoses/connectors you unplug.

---

🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Remove the engine appearance cover

• Lift the cover straight up to release the rubber grommets. Use a trim clip removal tool if it’s stuck.
• Set the cover aside where it won’t get stepped on.

Step 2: Decide which bank you’re doing (front bank vs rear bank)

• The “front bank” is the side closest to the radiator; coils are usually easy to access.
• The “rear bank” is closer to the firewall; on your Traverse, access typically requires removing the upper intake (plenum).

Step 3: Replace front-bank ignition coils (radiator side)

• Unplug the coil electrical connector by lifting the lock tab with a pick tool, then press the release and pull the connector straight off.
• Remove the coil hold-down bolt using a 10mm socket and 1/4" drive ratchet.
• Twist the coil slightly and pull it straight up to remove it from the spark plug.
• If using dielectric grease (a silicone grease that helps prevent moisture/corrosion), apply a tiny dab inside the new coil boot.
• Install the new coil by pushing it straight down until fully seated.
• Reinstall the hold-down bolt and Torque to 10 Nm (89 in-lb) using an inch-pound torque wrench.
• Reconnect the electrical connector until it clicks/locks.
• Repeat for the other front-bank cylinders you’re replacing.

Step 4: Remove the air intake duct (for rear-bank access)

• Loosen the hose clamps with an 8mm socket and 1/4" drive ratchet.
• Disconnect any attached small breather/PCV hoses by releasing clamps with a flat-blade screwdriver.
• Lift the duct out and set it aside.

Step 5: Remove the upper intake manifold (plenum) (rear-bank access)

• Unplug the throttle body connector and any sensors on the upper intake using a pick tool to release locks.
• Disconnect vacuum/PCV hoses from the upper intake (label them with painter’s tape).
• Remove the upper intake bolts using a 10mm socket, 3/8" drive ratchet, and a 6" extension.
• Lift the upper intake straight up and out. Don’t drop anything into the ports.
• Remove and discard the old upper intake gaskets; install new gaskets from the upper intake manifold gasket set.

Step 6: Replace rear-bank ignition coils (firewall side)

• Unplug each coil connector using a pick tool (release the lock, then pull off).
• Remove each coil hold-down bolt using a 10mm socket and 1/4" drive ratchet.
• Pull coils straight up, install new coils, then reinstall bolts.
• Torque to 10 Nm (89 in-lb) for each coil bolt using an inch-pound torque wrench.
• Reconnect all coil connectors until they click.

Step 7: Reinstall the upper intake manifold

• Carefully set the upper intake back into place over the new gaskets.
• Start all bolts by hand first to prevent cross-threading.
• Tighten the upper intake bolts evenly in a crisscross pattern using a 10mm socket and 3/8" drive ratchet.
• Torque to 25 Nm (18 ft-lb) using a foot-pound torque wrench.
• Reconnect all vacuum/PCV hoses and electrical connectors (use your labels).

Step 8: Reinstall the air intake duct and engine cover

• Reinstall the intake duct and tighten clamps using an 8mm socket. Make sure it’s fully seated to prevent a vacuum leak.
• Reinstall the engine cover by pressing it down onto the grommets.
• 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.
• Listen for hissing (a vacuum leak). If you hear it, re-check intake duct seating and hose connections.
• If the check-engine light was on, scan and clear codes, then confirm they do not return after a short drive.
• Test drive 10-15 minutes and re-check for any fuel/air smells or warning lights.

---

💰 DIY vs Shop Cost

Shop Cost: $250-$700 (parts + labor) (higher if rear bank is involved)

DIY Cost: $60-$420 (parts only)

You Save: $190-$280+ by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 1.0-2.5 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.