2012 Subaru Impreza Owner's Manual - Page 463

& Fuel: GAS STATION REFERENCE & Fuel octane rating: This octane rating is the average of the Research Octane and Motor Octane numbers and is commonly referred to as the Anti Knock Index (AKI). Refer to "Fuel octane rating" F7-3. ! Turbo models except STI Use premium unleaded gasoline with an octane rating of 91 AKI (95 RON) or higher. If premium unleaded gasoline with an octane rating of 91 AKI (95 RON) is not available, regular unleaded gasoline with octane rating of 87 AKI (90 RON) or higher may be temporarily used. For optimum engine performance and driveability, it is required that you use premium grade unleaded gasoline with an octane rating of 91 AKI (95 RON) or higher. ! STI The engine is designed to operate at maximum performance using unleaded gasoline with an octane rating of 93 AKI (98 RON) or higher. If 93 AKI (98 RON) fuel is not readily available in your area, unleaded gasoline with an octane rating of 91 AKI (95 RON) may be used with no detriment to engine durability or driveability. However, you may notice a slight decrease in maximum engine performance while using 91 AKI (95 RON) fuel. Use of 91 AKI (95 RON) fuel will not affect your warranty coverage. & Fuel capacity: 16.9 US gal (64 liters, 14.1 Imp gal) & Engine oil: Use only the following oils. . ILSAC GF-4 or GF-5, which can be identified with the ILSAC certification mark (Starburst mark) . or API classification SN or SM with the words "ENERGY CONSERVING" or "RESOURCE CONSERVING" For the complete viscosity requirements, refer to "Engine oil" F12-5. & Engine oil capacity: 4.4 US qt (4.2 liters, 3.7 Imp qt) & Cold tire pressure: Refer to "Tires" F12-9.