Subaru Outback Manuals 2018 Outback Owner's Manual | Page 283

Starting and operating/Fuel Fuel S07AA CAUTION Use of a fuel which is low in quality or use of an inappropriate fuel additive may cause damage to the engine and/or fuel system. & Fuel requirements S07AA01 The engine is designed to operate using unleaded gasoline with an octane rating of 87 AKI (90 RON) or higher. ! Fuel octane rating S07AA0103 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. See your dealer or a qualified service technician if you use a fuel with the specified octane rating and your vehicle knocks heavily or persistently. ! RON S07AA010301 This octane rating is the Research Octane Number. ! AKI S07AA010302 This octane rating is the average of the Research Octane and Motor Octane num- bers and is commonly referred to as the Anti Knock Index (AKI). ! Unleaded gasoline S07AA0104 The neck of the fuel filler pipe is designed to accept only an unleaded gasoline filler nozzle. Under no circumstances should leaded gasoline be used because it will damage the emission control system and may impair driveability and fuel economy. ! California fuel S07AA0105 If your vehicle was certified to California Emission Standards as indicated on the underhood tune-up label, it is designed to optimize engine and emission control system performance with gasoline that meets the clean burning low-sulfur Cali- fornia gasoline specifications. If you live in any other state than California, your vehicle will operate on gasoline meeting Federal specifications. Gasoline sold out- side California is permitted to have higher sulfur levels, which may affect the perfor- mance of your vehicle’s catalytic converter and may produce a sulfur exhaust odor or smell. SUBARU recommends that you try a different brand of unleaded gasoline having lower sulfur to determine if the problem is fuel related before returning 7-3 your vehicle to an authorized dealer for service. The CHECK ENGINE warning light/malfunction indicator light may also turn on. If this occurs, return to your authorized SUBARU dealer for diagnosis. If it is determined that the condition is caused by the type of fuel used, repairs may not be covered by your warranty. ! MMT S07AA0106 Some gasoline contains an octane-enhan- cing additive called MMT (Methylcyclo- pentadienyl Manganese Tricarbonyl). If you use such fuels, your emission control system performance may deteriorate and the CHECK ENGINE warning light/mal- function indicator light may turn on. If this happens, return to your authorized SUBARU Dealer for service. If it is determined that the condition is caused by the type of fuel used, repairs may not be covered by your warranty. ! Gasoline for cleaner air S07AA0107 CAUTION Do not let fuel spill on the exterior surfaces of the vehicle. Fuels con- taining alcohol may cause paint damage, which is not covered under the SUBARU Limited Warranty. Your use of gasoline with detergent ad- – CONTINUED –