Should the Buick Business Vehicle Use 92 or 95 Octane Gasoline?
1 Answers
Buick business vehicles can use 95 octane gasoline. This gasoline grade is recommended in the vehicle's official user manual. In addition to checking the appropriate gasoline grade in the user manual, the fuel cap of a Buick business vehicle will also indicate the recommended grade. Generally, 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. If the compression ratio is higher, 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 grade, 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 a Buick business vehicle occasionally uses the wrong gasoline grade, simply switch back to the correct grade after consumption. However, long-term use of the wrong gasoline grade can have the following effects: Using a higher octane gasoline in a vehicle designed for lower octane will not cause damage, but the increased octane number can alter the fuel's ignition point, leading to delayed combustion in the engine. This results in reduced engine power and thermal efficiency, manifesting as poorer performance. Using lower octane gasoline in a vehicle designed for higher octane can cause engine knocking. The significantly lower octane number reduces the fuel's ignition point, causing premature ignition during the compression stroke. If combustion occurs before the spark plug fires, resistance is generated during the upward stroke. This resistance makes the engine run very unstably. Mild knocking may only increase noise without significant engine damage, but severe knocking indicates serious engine conditions, affecting not only driving stability but also causing abnormal wear on pistons and cylinders, and even cylinder scoring in extreme cases.