What is the impact of using 95 gasoline in a car designed for 92?

[VonNora]

Using 95 gasoline in a car designed for 92 can affect the spark plugs and cylinders to some extent. Here are the specific details about refueling cars: 1. Gasoline grade explanation: Although 95 gasoline has higher anti-knock properties and power performance, vehicles designed for lower grades should not blindly use higher-grade gasoline. Higher grades are more suitable for engines with larger compression ratios, while engines designed for 92 gasoline usually have smaller compression ratios. Using 95 gasoline may increase engine knocking. 2. Avoid mixing grades: Different grades of gasoline should not be mixed, such as mixing 92 and 95 gasoline. Long-term use may also have certain effects on the engine, and may even lead to engine carbon deposits, increased fuel consumption, and other phenomena.

[LaAliyah]

I've been driving for many years and have researched fuel issues. Mixing 92 and 95 octane gasoline has a significant impact on the engine, primarily due to knocking problems. 92 octane has a lower rating while 95 is higher. If the car engine is designed for 95 octane but accidentally filled with 92, the insufficient octane rating causes pressure fluctuations during combustion, leading to knocking sounds. This not only creates annoying noise but also affects engine lifespan, potentially damaging piston and valve components. High-performance cars or turbocharged engines are especially prone to issues. Conversely, economy cars designed for 92 octane won't have problems with 95, but it's a waste of money. Modern cars have knock sensors to detect issues and automatically adjust ignition timing to mitigate risks, but long-term reliance may create hidden dangers. One-time misfueling isn't a big concern—just refill with the correct fuel to dilute it. Frequent fuel mixing increases fuel consumption, reduces overall operating efficiency, and raises maintenance costs. Remember to regularly check fuel quality and strictly follow the manual for refueling—that's the most reliable approach.