How to Replace Ignition Coils on a 2020 Subaru Outback (Fix Misfire)
Step-by-step coil swap with required tools/parts, safety tips, OBD2 checks, and torque specs for 2020, 2021, 2022, 2023, 2024
How to Replace Ignition Coils on a 2020 Subaru Outback (Fix Misfire)
Step-by-step coil swap with required tools/parts, safety tips, OBD2 checks, and torque specs for 2020, 2021, 2022, 2023, 2024
🔧 Outback - Ignition Coil Replacement
Your Outback has one ignition coil per cylinder. A bad coil can cause a misfire (shaking, flashing check engine light, loss of power), and replacing the coil(s) restores proper spark.
Difficulty Level: Intermediate | Estimated Time: 1.0-2.0 hours
⚠️ Safety & Precautions
- ⚠️ Let the engine cool fully before starting; the exhaust and cylinder heads get very hot.
- ⚠️ Disconnect the negative battery cable before unplugging coils to prevent shorts.
- ⚠️ If the check engine light is flashing, avoid driving; it can damage the catalytic converter.
- ⚠️ Pull on electrical connectors by the plug body, not the wires.
🔧 Required Tools
You'll need the following tools for this repair:
- 10mm socket
- 1/4" ratchet
- 3" extension
- 6" extension
- Universal joint adapter
- Torque wrench (in-lb or low-range ft-lb)
- Flathead screwdriver
- Trim clip removal tool
- Needle-nose pliers
- OBD2 scan tool
- Nitrile gloves
- Safety glasses
- Fender cover
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Ignition coil - Qty: 1-4
- Dielectric grease - Qty: 1
📋 Before You Begin
- Park on level ground, shift to Park, and set the parking brake.
- Open the hood and install a fender cover to protect paint.
- Disconnect the battery: use a 10mm socket to remove the negative (–) cable and move it aside so it can’t spring back.
- Plan to replace coils one at a time. This prevents mixing up connectors.
🔨 Step-by-Step Instructions
Follow these steps in order:
Step 1: Remove the engine cover (if equipped)
- Grab the cover near the corners and pull upward to release the grommets.
- Set it aside where it won’t get stepped on.
Step 2: Make room to access the coils
- Left side (driver side) access: Use a flathead screwdriver to loosen intake hose clamps, then lift the intake snorkel/duct out of the way.
- Right side (passenger side) access: If access is tight, use a 10mm socket to remove the battery hold-down, then lift the battery out. It’s heavy—lift with your legs.
- If any plastic push-clips are in your way, remove them with a trim clip removal tool.
Step 3: Unplug the coil electrical connector
- Locate the coil on the side of the engine; it’s the small module bolted to the valve cover with a rubber boot going into the cylinder head.
- Press the connector lock tab and pull the connector straight off.
- If it’s stuck, gently help it with needle-nose pliers on the connector body (not the wires).
Step 4: Remove the ignition coil retaining bolt
- Use a 10mm socket, ratchet, and a 3" or 6" extension to remove the coil bolt.
- If the angle is awkward, add the universal joint adapter.
Step 5: Pull the coil out
- Twist the coil slightly, then pull it straight out to remove the boot from the spark plug.
- Check for oil in the spark plug tube. If you see oil, stop and address the leak before installing the new coil (oil can cause repeat misfires).
Step 6: Install the new coil
- Put a tiny dab of dielectric grease inside the end of the coil boot. (Dielectric grease is a non-conductive grease that helps prevent moisture and makes future removal easier.)
- Push the coil straight onto the spark plug until it fully seats.
- Reinstall the coil bolt using a 10mm socket, then tighten with a torque wrench: Torque to 6.4 Nm (4.7 ft-lbs).
Step 7: Reconnect the coil connector
- Push the connector on until you feel/hear it click.
- Lightly tug it to confirm it’s locked.
Step 8: Repeat for any other coils you’re replacing
- Replace coils one at a time so you don’t mix up connectors.
- If you’re chasing a misfire code, match the cylinder noted by your scan tool before replacing more parts.
Step 9: Reassemble what you removed
- Reinstall the battery and hold-down using a 10mm socket (if removed).
- Reinstall the intake duct/snorkel and tighten clamps with a flathead screwdriver.
- Reinstall the engine cover by lining it up and pressing downward.
Step 10: Reconnect the battery
- Reconnect the negative (–) cable and tighten with a 10mm socket.
✅ After Repair
- Start the engine and let it idle for 1-2 minutes. It should run smooth with no shaking.
- Use an OBD2 scan tool to clear any misfire codes, then road test for 10-15 minutes.
- Re-check that all intake clamps and electrical connectors are fully seated.
- If the same misfire returns, the next common checks are spark plugs, injector, and compression (diagnosis needed before buying more parts).
💰 DIY vs Shop Cost
Shop Cost: $250-$650 (parts + labor)
DIY Cost: $60-$400 (parts only)
You Save: $190-$250+ 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.
🎯 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.

















