What Type of Gasoline Should the Buick Envision Use?
2 Answers
The Buick Envision should use 92-octane gasoline, as recommended in the vehicle's official owner's manual. In addition to checking the appropriate gasoline grade in the owner's manual, you can also find it indicated on the fuel tank cap. Typically, the gasoline grade can also be determined based on the engine's compression ratio. Vehicles with an engine compression ratio between 8.6-9.9 should use 92-octane gasoline, while those with a compression ratio between 10.0-11.5 should use 95-octane gasoline. For higher compression ratios, 98-octane gasoline is recommended. However, with the application of new technologies, the compression ratio alone cannot determine the appropriate gasoline grade, as high compression ratio engines can also be tuned to use lower-octane gasoline. Other factors, such as ignition timing, turbocharging technology, and Atkinson cycle technology, also play a role. Generally, the higher the gasoline octane rating, the higher the octane number and the better the anti-knock performance. 92-octane gasoline contains 92% isooctane and 8% n-heptane, while 95-octane gasoline contains 95% isooctane and 5% n-heptane. If the Buick Envision occasionally uses the wrong gasoline grade, simply switch back to the correct grade after the current tank is used up. However, prolonged use of the wrong gasoline grade can have the following effects: Using a higher-octane gasoline in a vehicle designed for lower-octane fuel will not cause damage, but the increased octane number can alter the fuel's ignition point, leading to delayed combustion in the engine. This reduces the engine's power output and thermal efficiency, resulting in poorer performance. Using a lower-octane gasoline in a vehicle designed for higher-octane fuel can cause engine knocking. The significantly lower octane number lowers the fuel's ignition point, causing premature ignition during the compression stroke. If combustion occurs before the spark plug fires, resistance is created during the upward stroke. This resistance makes the engine run very unevenly. Mild knocking may only increase noise without significant engine damage, but severe knocking indicates serious engine conditions. The vibrations not only affect driving stability but can also cause abnormal wear on the pistons and cylinders, potentially leading to cylinder scoring in severe cases.
The Buick Envision generally recommends using 95-octane gasoline, and I have deeply experienced this. After years of driving, my Envision has always been fueled with 95-octane gas, and I’ve noticed the engine responds faster, accelerates smoothly, and feels more stable, especially during high-speed overtaking. The manufacturer’s manual also recommends this octane rating because the engine has a high compression ratio, and higher-octane fuel helps reduce knocking and protects core components. Occasionally, when fuel prices are lower, I’ve tried using 92-octane, but the car would shake slightly during startup, produce louder noises, and noticeably affect performance. Later, during maintenance, the technician also reminded me to stick with 95-octane to extend engine life and reduce major repair costs. Using the right fuel for daily commutes ensures fewer minor issues even after 50,000 kilometers, and the fuel consumption remains more economical and worry-free. In short, for the sake of the car, choosing 95-octane is definitely the right call.
