Should I use 92 or 95 octane gasoline for engines previously using 93 octane?
2 Answers
Both are acceptable. For vehicles previously using 93 octane, you may now use either 92 or 95 octane. However, try to avoid mixing different grades during the same refueling period - wait until the current tank is depleted before switching. Here are relevant details: 1. Note: Different octane ratings don't indicate differences in gasoline purity. The rating reflects the fuel's octane number - higher octane indicates better anti-knock performance (knocking refers to abnormal combustion that causes irregular cylinder pressure, potentially damaging the engine). This is why luxury vehicles typically require 97# gasoline. 2. Risks of mixing: Mixing gasoline grades may cause engine knocking. The compression ratio represents the cylinder's maximum to minimum volume ratio during piston movement. While high-compression engines deliver greater power and fuel efficiency, they're often less stable - mixing gasoline grades could lead to severe knocking.
As a seasoned driver with over two decades of experience, I always emphasize the importance of following the vehicle manual. If your car requires gasoline with an octane rating of 93 or above, never opt for 92. The lower octane level in 92-grade fuel can easily cause engine knocking—those rattling sounds aren't just noisy but also severely wear down the engine, with repairs often costing thousands. In my younger days, I tried saving money by using 92, only to end up with weaker performance and higher fuel consumption. Switching to 95 made a noticeable difference, delivering smoother and more stable acceleration. Here's an extra tip: After each refuel, take a moment to listen carefully to the engine during startup. Address any unusual sounds promptly. Stick to the recommended fuel grade and maintain regular engine care, and your car will run as reliably as new even after a decade.
