Can I Add 95 Octane Gasoline When There's Still 92 Octane Left in the Tank?

[CassidyFitz]

You can add 95 octane gasoline when there's still 92 octane left in the tank, but it is not recommended to mix them for a long time. Long-term mixing may increase the frequency of engine knocking and accelerate engine wear. Some people believe that higher-octane gasoline is better, but in fact, blindly using higher-octane gasoline can lead to more carbon deposits and does not make the engine cleaner. The cleanliness of gasoline is not determined by its octane rating but by national standards. The octane rating represents the gasoline's octane number. For example, 92 octane gasoline consists of approximately 92% isooctane and 8% n-heptane. Since isooctane has better anti-knock properties while n-heptane has poorer anti-knock properties, a higher octane rating indicates better anti-knock performance of the gasoline.