How to Replace Ignition Coils on a 2016 Subaru Legacy 2.5L (Misfire Fix Guide)
Step-by-step coil swap with required tools, parts list, safety tips, and coil bolt torque spec (6.4 Nm) for 2015, 2016, 2017, 2018, 2019
How to Replace Ignition Coils on a 2016 Subaru Legacy 2.5L (Misfire Fix Guide)
Step-by-step coil swap with required tools, parts list, safety tips, and coil bolt torque spec (6.4 Nm) for 2015, 2016, 2017, 2018, 2019
🔧 Legacy - Ignition Coil Replacement
Your Legacy uses one ignition coil per cylinder (4 total). Replacing a bad coil restores smooth running and prevents misfires that can damage the catalytic converter.
Assumption: Stock 2.5L engine with top-access coils (no aftermarket parts).
Difficulty Level: Intermediate | Estimated Time: 1.0-2.0 hours
⚠️ Safety & Precautions
- ⚠️ Work on a cool engine; coils sit near hot components.
- ⚠️ Disconnect the negative battery terminal to prevent accidental shorting.
- ⚠️ Do not pull on wiring; press the connector lock tab and pull the plug body.
- ⚠️ Keep dirt out of spark plug tubes; debris can cause misfires.
🔧 Required Tools
You'll need the following tools for this repair:
- 10mm socket
- 1/4" drive ratchet
- 3" extension (1/4" drive)
- 6" extension (1/4" drive)
- Torque wrench (2–20 Nm range)
- Flat trim tool
- Needle-nose pliers
- Flashlight
- Nitrile gloves
- Safety glasses
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Ignition coil - Qty: 1 (or Qty: 4 if replacing all)
- 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 fully.
- Disconnect the battery negative terminal using a 10mm socket and move the cable aside so it can’t spring back.
- Take a photo of hose/clip routing first.
🔨 Step-by-Step Instructions
Follow these steps in order:
Step 1: Remove intake pieces for access (as needed)
- Use a flat trim tool to pop up any plastic push-clips holding the intake snorkel/duct (if equipped).
- Use a 10mm socket and 1/4" drive ratchet to loosen the air duct clamps and remove the duct from the air box/throttle body area (set it aside).
- If the passenger-side coils feel tight to reach, remove the upper air box section using the 10mm socket and needle-nose pliers for hose clamps.
Step 2: Locate the ignition coils
- Use a flashlight to find the coils on top of each cylinder head (two on each side of the engine).
- Each coil sits in a spark plug tube and is held by a single small bolt.
Step 3: Unplug the coil electrical connector
- Press the connector lock tab and pull the connector straight off the coil.
- If it’s stuck, use a flat trim tool gently to help the tab release (don’t pry hard).
- Pull the connector body, not the wires.
Step 4: Remove the coil retaining bolt
- Use a 10mm socket, 3" extension, and 1/4" drive ratchet to remove the coil bolt.
- Set the bolt somewhere safe (it’s easy to drop).
Step 5: Remove the ignition coil
- Twist the coil slightly by hand to break the seal, then pull it straight up and out.
- If it’s tight, use slow rocking motion—do not use metal tools against the valve cover.
Step 6: Install the new ignition coil
- Apply a very small amount of dielectric grease inside the coil boot (the rubber end that seals to the spark plug). Dielectric grease is a non-conductive grease that helps prevent moisture and makes future removal easier.
- Push the new coil straight down into the spark plug tube until it fully seats.
Step 7: Reinstall and torque the coil bolt
- Thread the bolt in by hand first (prevents cross-threading).
- Tighten with a 10mm socket and then torque with a torque wrench (2–20 Nm range): Torque to 6.4 Nm (4.7 ft-lbs).
Step 8: Reconnect the electrical connector
- Push the connector on until it clicks.
- Gently tug-test the connector to confirm it’s locked.
Step 9: Repeat for remaining coils (if replacing more than one)
- Use the same 10mm socket, extensions, and procedure on the other cylinders.
- Replace coils in pairs if one side failed.
Step 10: Reinstall intake parts and reconnect battery
- Reinstall the air box/ducting and clamps using a 10mm socket.
- Reconnect the battery negative terminal using a 10mm socket.
✅ After Repair
- Start the engine and let it idle for 1–2 minutes; it should run smooth with no flashing check engine light.
- Take a short test drive and recheck for hesitation under light acceleration.
- If the check engine light stays on, the code may need to be cleared after the fix (a parts-store scanner can do this).
- Recheck that every coil connector is fully clicked in and that no hoses were left disconnected.
💰 DIY vs Shop Cost
Shop Cost: $250-$650 (parts + labor, depending on how many coils)
DIY Cost: $60-$400 (parts only, depending on how many coils)
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.

















