Can I add 95 gasoline when 92 is not used up?
2 Answers
You can add 95 gasoline when 92 is not used up. It does not have much adverse effect on the car and the engine itself, but due to the insufficiently high design compression ratio, the characteristics of 95 gasoline cannot be fully utilized, resulting in "delayed combustion" and increased fuel consumption. Here is a related introduction to the differences between 92 and 95 gasoline: 1. The content of n-heptane and isooctane is different. The two most basic components of gasoline are n-heptane and isooctane. Isooctane has strong anti-knock properties and is the sedative of gasoline, while n-heptane has strong combustibility and is the stimulant of gasoline. These two interact, and the higher the isooctane content, the stronger the anti-knock performance of the gasoline. 92 gasoline is gasoline with an octane rating of 92, suitable for mid-range cars (with relatively low compression ratios), while 95 gasoline has an octane rating of 95 and 3 heptane. 2. The higher the label, the stronger the anti-knock performance. The grade of gasoline is an indicator of anti-knock, which is basically unrelated to cleanliness, power, and combustion value. The higher the gasoline label, the stronger the ability to resist engine knocking. The biggest difference between 92 and 95 is that 95 is more resistant to knocking than 92.
After driving for so many years, I often encounter situations where there's still some 92-octane gasoline left in the tank before directly adding 95-octane, and I've never had any issues. Modern car designs are quite intelligent—the engine control unit automatically adjusts ignition timing to accommodate different fuel octane ratings. When gasoline is mixed, the system optimizes combustion to prevent knocking. Of course, if the mixing ratio is high, such as when only a small amount of 92 is left and a large quantity of 95 is added, the overall octane rating will be closer to 95, potentially resulting in smoother performance, though it may not significantly boost power. Only cars with high-compression ratio engines are more recommended to use higher-octane fuel. My advice is not to worry—feel free to mix as you like, since the car can handle it. Just remember to regularly maintain and inspect the fuel system to ensure everything operates normally. Overall, such mixing is quite common in daily driving and won't harm the engine.
