Is There a Problem with Mixing 95 and 92 Gasoline?

[StMiles]

92 and 95 gasoline can be mixed once or twice, but long-term mixing is not recommended. The meaning of gasoline grades: They only represent the octane rating, with 92-grade containing 92% and 95-grade containing 95%. The quality level of the gasoline is the same, so the effect of mixing is the neutralization of the octane rating. Therefore, the quality of the gasoline is the neutralization of the octane rating, resulting in a "mid-grade" gasoline. The difference between 92 and 95 gasoline: Lies in their methane values. Higher gasoline grades indicate better anti-knock properties. Luxury car engines, which have higher requirements for gasoline, need higher-grade gasoline, while regular cars can use 92-grade. Generally, higher-grade gasoline is better.

[ColeFitz]

Once I accidentally mixed 95 and 92 octane gasoline at the gas station, and the car felt much less powerful afterward. Different octane ratings have different anti-knock properties - 95 has better knock resistance while 92 is cheaper. Mixing them lowers the overall octane value, which may not meet your engine's design requirements. My car normally uses 95, and after mixing fuels, the engine made strange knocking sounds. Prolonged use could cause internal damage or carbon buildup. While occasional mixing won't cause major issues (just run through that tank), making it a habit would be terrible. Now I always check the fuel cap sticker before refueling to confirm the correct grade - better safe than sorry. Also, knock risk increases in high temperatures, especially in summer. In short, don't risk engine health to save a few bucks - car longevity is what really matters.

[LaKing]

I always prioritize safety, especially when driving with kids. Mixing 95 and 92 gasoline can pose risks because their anti-knock properties differ. Blending them lowers the overall octane rating, affecting engine ignition stability. If the car is designed for higher-octane fuel, mixed fuel may cause engine knocking, uneven power output, or even stalling—extremely dangerous on highways. Of course, a one-time mistake isn’t catastrophic; simply refuel with the correct grade afterward. Don’t underestimate this issue—long-term mixed fueling can damage oxygen sensors or catalytic converters, leading to repair costs far exceeding fuel savings. Make it a habit to stick to one fuel grade, cross-checking your car’s manual for compatibility. A little extra care prevents roadside emergencies.

[VonCole]

As someone who frequently works on cars, I've seen many issues caused by mixing fuel. The difference between 95 and 92 fuel lies in their octane ratings. Mixing them can make the fuel unstable, potentially causing the engine to run weakly or vibrate. This is harmful to performance. Using it once in the short term is acceptable, but you should run the tank empty and then return to the original fuel. However, don't make it a habit, as it can accelerate wear and tear.