Subaru BRZ Manuals 2014 BRZ Owner's Manual | Page 425

6-1. Specifications Fuel information 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 and you may hear some knocking (pinking) of an engine while using 91 AKI (95 RON) fuel. Use of 91 AKI (95 RON) fuel will not affect your warranty coverage. I Fuel tank opening for unleaded gasoline To help prevent incorrect fueling, your SUBARU has a fuel tank opening that only accommodates the special nozzle on unleaded fuel pumps. I If your engine knocks G Consult your SUBARU dealer. G You may occasionally notice light knocking for a short time while accelerating or driving uphill. This is normal and there is no need for concern. I Gasoline quality In very few cases, driveability problems may be caused by the brand of gasoline you are using. If driveability problems persist, try changing the brand of gasoline. If this does not correct the problem, consult your SUBARU dealer. I 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). Using a gasoline with a lower octane rating can cause persistent and heavy knocking, which can damage the engine. Do not be concerned if your vehicle sometimes knocks lightly when you drive up a hill or when you accelerate. Contact your SUBARU dealer if you use a fuel with the specified octane rating and your vehicle knocks heavily or persistently. 424