Should the Superb use 92 or 95 octane gasoline?
4 Answers
The Superb's engine has a high compression ratio, requiring higher-octane gasoline. It is recommended to use 95 octane gasoline to prevent knocking. The Škoda Superb cannot directly switch from 95 octane to 92 octane gasoline. The differences between 92 and 95 octane gasoline are as follows: Different anti-knock properties: The gasoline octane rating represents anti-knock performance, with higher numbers indicating better anti-knock capability. Different octane content: 92 octane gasoline consists of 92% isooctane and 8% n-heptane, while 95 octane contains 95% isooctane and 5% n-heptane. The slightly higher price of 95 octane gasoline is due to its greater proportion of isooctane.
To be honest, as a veteran Octavia owner with five years of driving experience, I can say with authority. The fuel cap clearly states 95-octane requirement—this isn't just some arbitrary manufacturer suggestion. The EA888 engine's high compression ratio makes it particularly prone to knocking with 92-octane fuel—you'll hear that unsettling pinging sound inside the engine. While it might not be noticeable on short trips, the engine shakes like a sieve on highways, with sluggish throttle response. I once stubbornly tried two tanks of 92—fuel consumption jumped by over 1L/100km, making it ultimately more expensive. Long-term use also clogs the catalytic converter much faster, and repairs cost far more than fuel savings.
Let's do the math from a car maintenance cost perspective. Although 95-octane gasoline is a few cents more expensive per liter, Volkswagen's 2.0T engine requires it to achieve its rated thermal efficiency. Last time during actual testing, using 95-octane saved 0.8 liters per 100 kilometers compared to 92-octane, which translates to a 4-cent lower cost per kilometer. What's worse, using lower-octane fuel doubles the carbon buildup rate in direct injection engines. My friend's Superb, which had been running on 92-octane long-term, showed pitted piston tops when the engine was opened at 30,000 km. The small savings ended up being completely spent at the repair shop.
It depends on the engine model. The 1.4T EA211 has a compression ratio of only 10:1. While using 92 octane might work in the short term, turbo engines operate at much higher temperatures than naturally aspirated ones. I've seen many 1.4T engines running on 92 during repairs, with severe injector coking issues and frequent 2-3 cranks for cold starts. As for 2.0T models, the official manual explicitly mandates 95 octane in red letters. With gas stations frequently running promotions where 95 is cheaper than 92, there's really no need to take the risk.
