How to Replace Ignition Coils on a 2014 Mazda CX-5 (Fix Misfire & Rough Idle)
Step-by-step DIY coil swap with tools list, parts, safety tips, and coil bolt torque specs (8–10 Nm) for 2022, 2023, 2024
How to Replace Ignition Coils on a 2014 Mazda CX-5 (Fix Misfire & Rough Idle)
Step-by-step DIY coil swap with tools list, parts, safety tips, and coil bolt torque specs (8–10 Nm) for 2022, 2023, 2024
đź”§ CX-5 - Ignition Coil Replacement
Your CX-5 uses one ignition coil per cylinder (4 total). Replacing a bad coil can fix misfires, rough idle, poor acceleration, and a flashing check-engine light.
Difficulty Level: Beginner | Estimated Time: 0.5–1.0 hours
⚠️ Safety & Precautions
- ⚠️ Work on a cool engine; coils sit on a hot cylinder head.
- ⚠️ Keep dirt out of the spark plug wells; debris can cause misfires.
- ⚠️ If the check-engine light was flashing, avoid driving until fixed.
- ⚠️ Battery disconnect is not required, but disconnect the negative cable if you’re worried about shorting a connector.
đź”§ Required Tools
You'll need the following tools for this repair:
- 10mm socket
- 1/4" ratchet
- 6" extension (1/4")
- Torque wrench (5–25 Nm range)
- Trim clip tool
- Small flathead screwdriver
- Flashlight
- Nitrile gloves
- Safety glasses
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Ignition coil - Qty: 4
- Dielectric grease - Qty: 1
đź“‹ Before You Begin
- Park on level ground and set the parking brake.
- Let the engine cool fully (at least 30–60 minutes if it was running).
- If disconnecting the battery: use a 10mm socket to remove the negative terminal and isolate it so it can’t spring back.
🔨 Step-by-Step Instructions
Follow these steps in order:
Step 1: Remove the engine cover (if equipped)
- Use a trim clip tool to gently pry up the cover corners if it’s tight.
- Lift straight up to release it from the rubber grommets, then set it aside. Pull up evenly—don’t twist hard.
Step 2: Locate the ignition coils
- Use a flashlight to find the 4 coils on top of the valve cover, each with an electrical connector and one retaining bolt.
Step 3: Unplug the coil electrical connector
- Use a small flathead screwdriver to help lift the lock tab (only if needed).
- Press the connector release tab and pull the connector straight back (don’t pull on the wires).
Step 4: Remove the coil retaining bolt
- Use a 10mm socket, 1/4" ratchet, and 6" extension (1/4") to remove the bolt.
- Place the bolt somewhere safe so it doesn’t fall into the engine bay.
Step 5: Remove the ignition coil
- Grip the coil body and pull straight upward while gently wiggling.
- If it’s stuck, keep the wiggle small—don’t pry hard on plastic.
Step 6: Install the new ignition coil
- Apply a tiny smear of dielectric grease inside the rubber boot. (Dielectric grease is a non-conductive grease that helps prevent moisture and makes future removal easier.)
- Push the new coil straight down until you feel it seat on the spark plug.
Step 7: Reinstall and torque the coil bolt
- Start the bolt by hand to avoid cross-threading.
- Use a torque wrench (5–25 Nm range) and 10mm socket: Torque to 8–10 Nm (71–89 in-lbs).
Step 8: Reconnect the coil connector
- Push the connector on until it clicks and is fully seated.
- Give it a gentle tug to confirm it’s locked.
Step 9: Repeat for the remaining coils
- Replace one coil at a time so you don’t mix up connectors.
Step 10: Reinstall the engine cover
- Align it with the mounting points and press straight down until it snaps in.
âś… After Repair
- Start the engine and let it idle for 1–2 minutes; it should run smoothly.
- Take a short test drive and check for hesitation under light acceleration.
- If the check-engine light stays on, the code may need to be cleared (a parts store can often scan it). If it flashes, stop driving and recheck connectors.
- Recheck for any tools left in the engine bay before closing the hood.
đź’° DIY vs Shop Cost
Shop Cost: $250–$550 (parts + labor)
DIY Cost: $120–$400 (parts only)
You Save: $130–$150 by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 0.7–1.0 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.


















