2021–2024 Ford F-150

2021-2024 Ford F-150 — Spark Plug Replacement

By Tom Becker ✓ Certified Mechanic · Published Sep 21, 2026 · Updated Oct 22, 2026

🔧🔧🔧 Advanced 1-3 hours $115 DIY

Save $335 by doing it yourself! Shop cost: $450

Quick answer: Spark Plug Replacement on a 2021–2024 Ford F-150 is rated Advanced and takes about 1-3 hours. You'll need 3 tools for this job, and parts cost about $115. This guide walks you through the full job step by step, including the mistakes to avoid.

Quick Video Tutorial

Parts You Need

Total Cost

$115.00

Part Name	Part Number	Price	Buy
Correct spark plug set for the gasoline/ICE engine in 2021-2024 Ford F-150 Hybrid; verify engine, heat range, gap, and VIN fitment	—	$115.00	Amazon
Coil-boot seals or ignition coils only if inspection finds damage Optional	—	$35.00	Amazon

About prices: shown prices are typical retail averages and change frequently; cheaper alternatives may be available. Confirm the current price before buying.

💡 Pro tip: Order all parts at once to save on shipping

Step-by-Step Instructions

Follow these steps carefully

Confirm engine and plug fitment

Plugs differ by engine: 2.7L/3.5L EcoBoost takes Motorcraft SP-594 (CYFS-12Y-PT), 0.030 in, pre-gapped — buy 6, never adjust. 5.0L V8 takes Motorcraft CYFS-12F-1X platinum — buy 8. Scan for P0300 misfires first.

🔧 Mechanic's note — Tom Becker

I never re-gap those EcoBoost finewire plugs — the tips are fragile and you'll ruin a $15 plug trying. They come set from the factory.

Cool and expose the plugs

Cool fully; disconnect the negative cable. Remove the engine cover. Rear EcoBoost coils hug the cowl — swivel sockets help. Late-build trucks use a revised washer-seat plug, so match what comes out.

Remove coils and clean wells

Unplug each coil, remove the hold-down bolt (89 in-lb on reinstall), lift the coil straight up. Blow/brush every well clean first — grit in deep EcoBoost wells scores cylinders. One cylinder at a time.

🔧 Mechanic's note — Ray Delgado

I've found that clean those wells before the plug comes out — one grain of grit dropped into an EcoBoost cylinder is a scored wall and an engine-out repair.

Install the new plugs

Read old plug deposits for boost-leak or oil clues. Start each new Motorcraft plug by hand — never an impact. Verify the 0.030 in EcoBoost gap without prying the finewire tips. Dab dielectric grease inside each coil boot.

Reconnect and verify

Reinstall coils, torque hold-downs, click every connector home. Refit cover and battery cable. Start, idle, then drive under light boost — smooth pull expected. Any stumble = loose coil connector, not the new plugs.

All Done!

Test your repair before closing everything up. If something doesn't work right, double-check your steps.

⚠️ Common Mistakes to Avoid

• Using the wrong plug or assuming a pre-gapped plug needs no verification
• Blowing debris into an open cylinder or plug well
• Cross-threading a plug or tightening it without a torque wrench
• Overusing anti-seize or dielectric grease on the plug threads
• Mixing coil connectors or ignoring a misfire after reassembly

Tools You'll Need

Metric/SAE socket set with extensions and swivel Spark-plug socket with rubber insert or magnet Torque wrench covering the plug range Compressed air or a soft brush, dielectric grease, gloves, and eye protection

Related Trouble Codes

P0300 Random/Multiple Cylinder Misfire Detected P0301 Cylinder 1 Misfire Detected P0302 Cylinder 2 Misfire Detected P0303 Cylinder 3 Misfire Detected P0304 Cylinder 4 Misfire Detected P0305 Cylinder 5 Misfire Detected P0306 Cylinder 6 Misfire Detected P0307 Cylinder 7 Misfire Detected

⚠️ Safety First!

• Informational DIY. EZ Car Fix is not a shop.
• Work on a cool engine and keep dirt out of the plug wells.
• Verify plug type, gap, reach, and torque in the exact service information; do not rely on a generic value.
• Do not pull on coil wiring, cross-thread plugs, or use an impact gun for installation.
• Stop if a plug is seized, the threads are damaged, or fuel/oil contamination indicates a larger fault. Spark-plug service is for an internal-combustion engine only; never apply it to an EV or Tesla.