Buick Enclave: Recommended Fuel. Gasoline Specifications (U.S. and Canada Only). California Fuel Requirements
Recommended Fuel
Use regular unleaded gasoline with a posted octane rating of 87 or higher. This is the recommended fuel grade for normal operation. Using gasoline with the correct octane rating helps the engine operate as designed and helps prevent abnormal combustion noise.
If the octane rating is less than 87, an audible knocking noise, commonly referred to as spark knock, might be heard when driving. Light spark knock may be more noticeable during acceleration, climbing hills, carrying load, or driving in hot weather. If this occurs, use 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. Continued heavy knocking can indicate a problem that should not be ignored, because it may affect engine performance and durability.
For everyday driving, the Buick Enclave does not require premium gasoline unless a specific condition or service recommendation calls for it. The most important point is to use clean, unleaded gasoline that meets the required octane and quality standards.
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. These specifications help ensure that the fuel has the proper characteristics for engine operation, emissions control, cold starting, and drivability.
Some gasolines contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT). The use of gasolines containing MMT is not recommended. See Fuel Additives for additional information.
Fuel that does not meet the proper specification may lead to drivability concerns, increased emissions, reduced spark plug life, or warning lights related to the emission control system. When possible, buy gasoline from reputable stations with good fuel turnover.
California Fuel Requirements
If the vehicle is certified to meet California Emissions Standards, it is designed to operate on fuels that meet California specifications. These fuels are formulated to support the vehicle’s emission control system and help it meet the requirements for which it was certified.
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 . 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.
When traveling, especially across states or regions with different fuel standards, use fuel from trusted retailers and choose gasoline that matches the requirements listed for the vehicle. Proper fuel selection helps the Buick Enclave maintain stable performance and helps protect emission-related components.
