Marsram Ignition Coil Pack & AP104 Iridium Spark Plug Kit for 2003-2007 Ford Focus 2.3L — 4-Coil 4-Plug Direct Replacement

Marsram Ignition Coil Pack FD505 bundled with AP104 iridium spark plugs — a direct-replacement ignition kit engineered to restore reliable spark, smoother idle, and responsive acceleration for compatible 2.0–2.3L Ford, Mazda, and Mercury engines.

This kit combines four high-conductivity ignition coils and four double-iridium spark plugs sized for a range of Focus, Escape, Transit Connect, Mazda3, Tribute and Mariner models. Each coil uses durable engineering plastics and epoxy encapsulation to resist heat and vibration, while tightly wound copper windings deliver fast, consistent spark energy. The iridium-tipped spark plugs reduce gap growth and promote efficient combustion for improved throttle response and easier cold starts. Always verify vehicle fit using your OEM part references or the vehicle-fit tool before purchase.

Will this coil pack and spark plug kit fit my vehicle?

Compatibility covers many 2.0–2.3L Ford, Mazda, and Mercury models from the early 2000s through 2013. The listing replaces multiple OEM and aftermarket numbers, so match one of those part references to confirm fitment.

• Fits Ford Focus (various trims) and certain Escape and Transit Connect years listed in product notes.
• Compatible with Mazda3 and Tribute 2.0–2.3L variants identified in applications.
• Replaces FD505, UF621, DG504, DG541, 4M5G12A366BC and other OEM numbers—check your vehicle’s part number.

How do the Marsram coils and iridium plugs improve engine performance?

The coils use high-conductivity copper windings for a quicker, stronger spark, and the epoxy-plastic housing resists heat-related degradation. The AP104 spark plugs use double iridium electrodes and a corrosion-resistant design that helps maintain optimal gap and combustion efficiency over time.

• Stronger, faster spark for more complete combustion under load.
• Iridium tips minimize electrode wear and preserve gap consistency.
• Durable housing limits heat damage and extends coil lifespan.

Is installation straightforward and what tools are required?

These ignition coils and spark plugs are manufactured to meet or exceed original equipment design, so they install like stock parts. Basic hand tools and torque specifications are all you need; follow factory service procedures for safe removal and installation.

• Requires basic socket set, torque wrench, and dielectric grease (optional).
• Replace coils and plugs one cylinder at a time to preserve firing order.
• Observe manufacturer torque specs and clearance/gap settings if applicable.

What warranty and customer support does Marsram provide?

The product is sold as a complete four-coil and four-plug kit with a one-year aftermarket warranty against manufacturing defects. Marsram encourages customers to contact support promptly if any issue arises so they can assist with troubleshooting or replacement.

• Includes a one-year limited warranty from the date of purchase.
• Package contains 4 ignition coils and 4 AP104 spark plugs.
• Customer service available for fitment questions and defect claims.

Who this is for: Mechanics, DIY enthusiasts, and drivers who own compatible Ford, Mazda, or Mercury 2.0–2.3L vehicles and need a reliable replacement ignition kit that balances durability, performance, and value. Choose this Marsram kit when you want OEM-style fitment, improved spark consistency, and iridium spark plugs designed to keep your engine firing cleanly between service intervals.