Should Skoda Use 95 or 92 Octane Gasoline?
2 Answers
According to the official car manual recommendation, Skoda should use 92 octane gasoline. In addition to checking the suitable gasoline grade in the car manual, Skoda owners can also find this information on the fuel tank cap, which is usually marked there. Typically, the gasoline grade can also be determined based on the engine's compression ratio. Cars 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. However, with the application of new technologies, the compression ratio alone cannot determine the gasoline grade. Even high compression ratio engines can be tuned to use lower octane gasoline. This is because, apart from the compression ratio, 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 Skoda occasionally uses the wrong gasoline grade, simply switch back to the correct grade after the current tank is used up. However, long-term use of the wrong gasoline grade can have the following effects: For vehicles recommended to use lower octane gasoline, using a higher octane grade will not cause damage, but the increase in octane number will alter the fuel's ignition point, leading to delayed combustion in the engine. This means both the engine's power output and thermal efficiency will decrease, resulting in poorer performance. For vehicles recommended to use higher octane gasoline, using a lower octane grade can cause engine knocking. This happens because the significantly lower octane number reduces the gasoline's ignition point, causing premature ignition during the compression stroke. If the fuel ignites before the spark plug fires, resistance will occur during the upward stroke. This resistance makes the engine run very unstably. If the knocking is mild, it may only increase noise without obvious damage to the engine. However, noticeable knocking indicates severe engine conditions, affecting not only driving stability but also causing abnormal wear on pistons and cylinders, and in severe cases, even cylinder scoring.
I've been driving a Skoda for several years now, and based on my experience, most Skoda models are recommended to use 95-octane unleaded gasoline. As they belong to the Volkswagen Group, their engines are designed with high compression ratios. Using lower-octane 92 gasoline can easily cause knocking—that abnormal vibration sound in the engine—and prolonged use may affect power output and engine lifespan. I've encountered owners who opted for cheaper 92-octane fuel, only to find their cars sluggish at startup and with increased fuel consumption, ultimately spending more on repairs later. So, it's best to follow the user manual, which clearly states the octane rating requirements. 95-octane burns more stably and is more environmentally friendly. Of course, if you're at a remote gas station with only 92-octane available, it's fine for short-term emergencies, but don't make it a habit. In conclusion, for the sake of my car's safety and performance, I stick to 95-octane gasoline.
