MAS Ignition Coil Set for Ford 4.6L/5.4L V8 - Set of 8 Brown DG521 Boots with Motorcraft SP-509 Plugs

Complete ignition kit: eight MAS ignition coils with brown DG521 boots paired with eight Motorcraft SP-509 spark plugs for Ford 4.6L and 5.4L V8 engines.

If your Ford V8 is showing misfires, rough idle, or reduced throttle response, replacing the full set of coils and plugs is a practical way to restore reliable spark delivery. This MAS kit bundles eight direct-fit ignition coils with brown boots (DG521) and Motorcraft SP-509 spark plugs, supplying all components needed for a full ignition system refresh on many Ford models from the late 2000s to early 2010s.

How do I know these coils fit my vehicle?

Fitment depends on engine size and the coil boot color in your OEM system. These coils are intended for Ford 4.6L and 5.4L V8 engines in the listed model years, and specifically match vehicles that use brown DG521 boots.

• Check your current coil boot color—this kit is for brown boots (DG521).
• Compatible models: select Expedition, Explorer, F-150, F-250, F-350, F-450, F-550, Mustang, Lincoln Navigator, Mark LT, Mercury Mountaineer.
• Compare OE part numbers like C1659, DG521, SP509 to ensure match.

What improvements will I notice after installing this kit?

Replacing worn coils and spark plugs can reduce misfires, improve throttle response, and stabilize idle. Because the kit replaces all eight ignition points, it restores uniform spark strength across cylinders rather than addressing symptoms piecemeal.

• Smoother idle and fewer engine hesitations.
• More consistent acceleration and improved combustion balance.
• Reduced risk of catalytic converter damage from unburned fuel due to misfires.

Are these coils a direct replacement and durable enough for everyday use?

Yes—these MAS coils are built to be direct-fit replacements and use high-heat resistant compounds for the on-plug boot. They are designed for straightforward installation and long-term durability under typical engine temperatures.

• High-grade materials and heat-resistant boot compound for longevity.
• Engineered for specific Ford V8 applications to ensure correct electrical output.
• Sold as a full set with Motorcraft SP-509 plugs to simplify maintenance.

What should I check before ordering to avoid the wrong part?

Because Ford used different coil designs partway through some model years, visually confirming your current coil boot color and OEM part numbers is important. If your original coils are black (DG511), this brown-boot kit will not match.

• Inspect the coil boot color on your vehicle—brown = DG521 kit, black = other kit.
• Compare OE part numbers like 8L3Z-12029-A, C1659, SP509 listed with your service manual or parts sticker.
• If unsure, consult a VIN-based parts lookup or a trusted mechanic before purchase.

Who is this for? This MAS ignition coil and spark-plug set is geared toward Ford owners and independent mechanics who want a full, like-for-like ignition refresh for 4.6L and 5.4L V8 engines. It’s especially suited to vehicles whose original coils use brown boots (DG521), and for anyone preferring a complete eight-cylinder replacement to prevent future misfires and uneven cylinder performance. The kit pairs direct-fit MAS coils with Motorcraft SP-509 plugs and includes one year limited coverage, making it a practical option for routine maintenance or restoration projects on compatible Ford trucks and SUVs.