2014 Buick Verano Owner Manual - Page 245

Driving and Operating 9-49 Fuel Use of the recommended fuel is an important part of the proper maintenance of this vehicle. When driving in the U.S., to help keep the engine clean and maintain optimum vehicle performance, we recommend using TOP TIER Detergent Gasolines. See www.toptiergas.com for a list of TOP TIER Detergent Gasolines. Recommended Fuel For vehicles with a 2.0L engine, use premium unleaded gasoline with a posted octane rating of 91 or higher. Regular unleaded gasoline rated at 87 octane or higher can be used, but acceleration could be reduced, and an audible knocking noise may be heard. If the octane is less than 87, a heavy knocking noise may be heard. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, the engine could be damaged. If heavy knocking is heard when using gasoline with a higher octane rating, the engine needs service. For vehicles with a 2.4L engine, use regular unleaded gasoline with a posted octane rating of 87 or higher. If the octane rating is less than 87, an audible knocking noise may be heard. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. If heavy knocking is heard when using gasoline with a higher octane rating, the engine needs service. Use of Seasonal Fuels Use summer and winter fuels in the appropriate season. Driving or starting could be affected if the incorrect fuel is used. Drive the vehicle with the engine running until the fuel is a half tank or less, then refuel with the current seasonal fuel. Prohibited Fuels Gasolines containing oxygenates, such as ethers and ethanol, as well as reformulated gasolines are available in some cities. If these gasolines comply with the previously described specification, then they are acceptable to use. However, E85 and other fuels containing more than 15% ethanol must be used only in FlexFuel vehicles.