Motorcraft SP-594 Iridium Spark Plug

The SP-594 (Ford dealer part number CYFS-12Y-RT3) is the current Ford OEM spark plug across the gasoline EcoBoost engine families: 2.7L EcoBoost in the F-150 (2015+), Edge, and Bronco; 3.5L EcoBoost in the F-150 (2017+) and Expedition (2018+); 2.3L EcoBoost in the Explorer, Mustang, Bronco, and Ranger; and 2.0L EcoBoost in the Escape, Edge, Maverick, and Bronco Sport. It also covers Lincoln Nautilus, Continental, and MKX EcoBoost applications. Always confirm your specific engine via Ford's application guide or your owner's manual before buying.

Amazon's catalog shows 'Top Material Type: Copper' and 'Core Material: Copper' for the Motorcraft single-plug listing, which is an Amazon database entry error. The SP-594 is an iridium center electrode plug with a platinum-tipped ground electrode, per Ford's OEM designation (CYFS-12Y-RT3) and confirmed by third-party reseller descriptions. This same catalog error type appears on other Motorcraft spark plug listings.

Ford rates the SP-594 at up to 100,000 miles. Community reviews confirm reaching 80,000-100,000 miles with positive results on 2.7L EcoBoost applications. The SP-594 carries a longer rated interval than the SP-534/SP-580X 60,000-mile plugs used in the 3.5L EcoBoost and 5.0L Coyote applications.

The SP-594 (CYFS-12Y-RT3) supersedes and replaces the earlier SP-542 and SP-578. If your vehicle's service record or Ford parts lookup shows SP-542 or SP-578 as the OEM plug, the SP-594 is the current Ford replacement.

Yes, the single-plug Motorcraft listing is an Amazon add-on item requiring a minimum qualifying order or Subscribe and Save to purchase standalone. A 6-pack option (sold by OverstockDirect) is available separately as a standard in-stock listing and may be more convenient if you need a full set.