The COBB Air/Oil Separator for the 20162018 Ford Focus RS is a purpose-built upgrade that eliminates oil vapor from the intake system, ensuring your EcoBoost engine runs cleaner, stronger, and more reliably. Designed and developed in-house, this AOS system offers a seamless installation that integrates with OEM components while meeting strict emissions standards.

Fords 2.3L EcoBoost engine presents a challenge when it comes to adding an oil separator, so COBB engineered a custom solution using a spacer plate made from 33% glass-filled nylon. This injection-molded plate fits perfectly between the factory breather and engine block, and includes a COBB-supplied OEM gasket to guarantee a secure, leak-free seal.

Once installed, the COBB AOS routes crankcase vapors through a swirl pot and a series of baffles inside the billet aluminum canister. This process condenses heavier oil particles into liquid form, which is then automatically returned to the engine via a drain-back line. The result: cleaner intake valves, reduced carbon buildup, and more consistent engine performance with less maintenance.

Finished in a bright black anodizing with a laser-etched COBB logo, the canister also includes additional internal baffling for optimized efficiency. Whether you’re daily driving or pushing your RS at the track, this system helps preserve octane rating and protect against detonationmaking it an essential performance upgrade.

This product is 50-state legal and emissions-compliant under CARB Executive Order D-660-123.