What grade of gasoline should the new Volkswagen Sagitar use?

[JonathanDella]

Volkswagen Sagitar should use 95-octane gasoline, as recommended in the vehicle's official user manual. In addition to checking the appropriate gasoline grade in the user manual, you can also find it on the fuel tank cap, which will be clearly marked. Generally, the gasoline grade can also be determined based on the engine's compression ratio. Cars with a 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 use of new technologies, the compression ratio alone cannot determine the gasoline grade. High compression ratio engines can also be tuned to use lower-octane gasoline due to other influencing factors such as ignition timing, turbocharging technology, and Atkinson cycle technology. 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 the wrong gasoline grade is occasionally used in the Volkswagen Sagitar, simply switch back to the correct grade after consumption. However, long-term use of the wrong gasoline grade can have the following effects: For vehicles that recommend a lower grade, using a higher grade 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. For vehicles that recommend a higher grade, using a lower grade 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 ignites, resistance will develop 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 in extreme cases, cylinder scoring.