2012 Buick Regal Owner Manual - Page 269

Driving and Operating See Fuel E85 (85% Ethanol) on page 9￿49. For all other vehicles, use only the unleaded gasoline described under Recommended Fuel on page 9￿47. higher, but the vehicle's acceleration could be slightly reduced, and a slight audible knocking noise, commonly referred to as spark knock, might be heard. If the octane is less than 87, a heavy knocking noise might be heard when driving. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you could damage the engine. If heavy knocking is heard when using gasoline rated at 87 octane or higher, the engine needs service. 9-47 containing MMT. See Fuel Additives on page 9￿48 for additional information. Recommended Fuel If the vehicle has the 2.4L L4 engine (VIN Code K) or the 2.4L L4 engine (VIN Code R), 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, commonly referred to as spark knock, might be heard when driving. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. If heavy knocking is heard when using gasoline rated at 87 octane or higher, the engine needs service. If the vehicle has the 2.0L L4 engine (VIN Code V), use premium unleaded gasoline with a posted octane rating of 91 or higher. You can also use regular unleaded gasoline rated at 87 octane or California Fuel Requirements If the vehicle is certified to meet California Emissions Standards, it is designed to operate on fuels that meet California specifications. See the underhood emission control label. If this fuel is not available in states adopting California Emissions Standards, the vehicle will operate satisfactorily on fuels meeting federal specifications, but emission control system performance might be affected. The malfunction indicator lamp could turn on and the vehicle might fail a smog￿check test. See Malfunction Indicator Lamp on page 5￿15. If this occurs, return to your authorized dealer for diagnosis. If it is determined that the condition is caused by the type of fuel used, repairs might not be covered by the vehicle warranty. Gasoline Specifications (U.S. and Canada Only) At a minimum, gasoline should meet ASTM specification D 4814 in the United States or CAN/ CGSB￿3.5 or 3.511 in Canada. Some gasolines contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT). We recommend against the use of gasolines