Can 92 and 95 gasoline be mixed?
2 Answers
92 gasoline and 95 gasoline cannot be mixed because their isooctane content is different. 92 gasoline is suitable for engines with low compression ratios, while 95 gasoline is suitable for engines with high compression ratios. If 92 gasoline is added to a car that should use 95 gasoline, abnormal combustion may occur, leading to knocking. Knocking not only damages the combustion chamber but also directly affects the normal operation of the engine, and in severe cases, may cause engine damage. If 95 gasoline is added to a car that should use 92 gasoline, although it will not damage the engine, 95 gasoline is more expensive than 92 gasoline, resulting in waste. The difference between 92, 95, and 98 gasoline: Standard gasoline is composed of isooctane and n-heptane. Isooctane has good anti-knock properties, and its octane number is defined as 100; n-heptane has poor anti-knock properties and is prone to knocking in gasoline engines, so its octane number is defined as 0. If the gasoline is labeled as 92, it means that this gasoline has the same anti-knock properties as standard gasoline containing 92% isooctane and 8% n-heptane. The same principle applies to 95 and 98 gasoline. What to do if the wrong gasoline is added: If gasoline with a higher octane number than specified is added, for example, adding 95 gasoline when 92 is specified, simply switch back to 92 gasoline after the current fuel is consumed. If gasoline with a lower octane number than specified is added, for example, adding 92 gasoline when 95 is specified, you can add a high anti-knock fuel additive. Of course, you can also directly drain the fuel and refill with 95 gasoline. To find out which gasoline your car requires, you can check the car's user manual or the fuel label on the fuel tank cap.
I've been driving for over 30 years. When I was young, I thought mixing 92 and 95 octane gasoline was fine. Later, I noticed the engine started knocking constantly and fuel consumption skyrocketed. During repairs, the mechanic explained that inconsistent octane ratings cause knocking and piston damage. Since then, I strictly follow the manual's fuel recommendations. If the manual specifies 95, I use 95. An occasional mix might be tolerable, but don't make it a habit. An engine is like a human body needing consistent nutrition - inconsistent fuel quality affects its performance and longevity. With current high fuel prices, I understand wanting to save money, but repairs cost more. My advice: don't take risks. Playing it safe makes long journeys more reliable.
