Can I add 95 gasoline when 92 gasoline hasn't run out yet?
1 Answers
92 gasoline and 95 gasoline cannot be mixed. Occasionally adding the wrong gasoline grade only requires switching back to the correct gasoline grade after use. However, if the wrong gasoline grade is added for a long time, it will have the following effects: For vehicles that recommend low-grade gasoline, accidentally adding high-grade gasoline will not cause damage, but the increase in octane number will change the ignition point of the fuel, leading to delayed combustion in the engine. This means the engine's power output and thermal efficiency will both decrease, and the actual feedback experience is reduced power; For vehicles that recommend high-grade gasoline, using low-grade gasoline will cause engine knocking. Because the octane number is much lower, the lower ignition point of the gasoline will cause it to ignite prematurely during the compression stroke. If the gasoline ignites before the spark plug fires during the compression stroke, resistance will occur during the upward stroke. This resistance will make the engine run very unstably. If it's mild knocking, it only increases noise and does not cause obvious damage to the engine. If there is noticeable knocking, it indicates the engine's operating condition is already very severe. The vibration not only affects driving stability but also causes abnormal wear on the pistons and cylinders, and in severe cases, can lead to cylinder scoring. In addition to checking the appropriate gasoline grade in the car's manual, you can also check it on the fuel tank cap, which will also indicate the recommended grade. Usually, the gasoline grade can also be determined based on the engine's compression ratio. Cars with an engine compression ratio between 8.6-9.9 should use 92 gasoline, cars with a compression ratio between 10.0-11.5 should use 95 gasoline, and if the compression ratio is higher, 98 gasoline should be used. However, with the use of some new technologies, the gasoline grade cannot be determined solely based on the compression ratio. High compression ratio engines can also be tuned to use low-grade gasoline. This is because, in addition to the compression ratio, other factors such as ignition timing, turbocharging technology, and Atkinson cycle technology also play a role. Generally, the higher the gasoline grade, the higher the octane number, and the better the anti-knock performance. 92 gasoline contains 92% isooctane and 8% n-heptane, while 95 gasoline contains 95% isooctane and 5% n-heptane.
