Should the Changan Yidong use 92 or 95 octane gasoline?
4 Answers
According to the official vehicle manual recommendation, the Changan Yidong should use 92 octane gasoline. In addition to checking the appropriate gasoline grade in the vehicle manual, you can also find it marked on the fuel tank cap of the Changan Yidong. Typically, the gasoline grade can also be determined based on the engine's compression ratio. Vehicles with an engine compression ratio between 8.6-9.9 should use 92 octane gasoline, while those with a compression ratio between 10.0-11.5 should use 95 octane gasoline. However, with the application of some new technologies, the gasoline grade cannot be solely determined by the compression ratio. High compression ratio engines can also be tuned to use lower octane gasoline. This is because, besides 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 octane gasoline contains 92% isooctane and 8% n-heptane, while 95 octane gasoline contains 95% isooctane and 5% n-heptane. If the Changan Yidong occasionally uses the wrong gasoline grade, simply switch back to the correct grade after consumption. However, long-term use of the wrong gasoline grade can have the following effects: For vehicles recommended to use lower octane gasoline, using a higher octane grade will not cause damage, but the increase in octane number may alter the fuel's ignition point, leading to delayed combustion in the engine. This results in reduced engine power and thermal efficiency, with the practical feedback being poorer performance. For vehicles recommended to use higher octane gasoline, using a lower octane grade can cause engine knocking. Due to the significantly lower octane number, the gasoline's ignition point decreases, causing premature ignition during the compression stroke. If combustion occurs before the spark plug fires during the compression stroke, resistance will arise during the upward stroke. This resistance makes the engine run very unstably. If the knocking is imperceptible, it only increases noise without obvious damage to the engine. However, noticeable knocking indicates severe engine conditions, affecting not only driving stability but also causing abnormal wear on pistons and cylinders, and in severe cases, cylinder scoring.
I think for the Changan Eado, when you open the fuel tank cap, you can see the manufacturer's recommendation label, which clearly states that 92-octane gasoline is recommended. I've been driving the Eado for three years, always using 92 with no issues at all. 92 is cheaper and more economical, so why spend extra on 95? The engine was designed to match the anti-knock performance of 92-octane, which is perfectly adequate for normal driving. However, if you frequently drive on highways or have modified the engine, then 95-octane might be worth considering. But for the average user, there's really no need to overthink this. Following the manual is the safest bet, and the money saved on fuel can be better spent on a few more maintenance services.
It depends on your budget and personal habits! My Changan Eado runs on 92-octane fuel for daily city commuting, which offers lower fuel consumption and reduced expenses – saving nearly 100 yuan per month on gas. Honestly, the power difference between 92 and 95 is negligible unless measured with professional equipment. Of course, if you're particularly meticulous about your car or frequently drive on mountainous slopes, switching to 95 might make the engine sound slightly smoother. But the key is regular maintenance – changing the fuel filter more often matters far more than the octane rating. I recommend beginners start with 92-octane and adjust based on their driving experience later.
Straight to the point: 92 octane is perfectly sufficient. The engine parameters of the Changan Eado were originally designed for 92 octane, and the fuel cap label clearly indicates that 92 octane gasoline is suitable. Not only is 95 octane more expensive, but long-term use may actually lead to incomplete combustion and wasted money. For daily driving, there's really no need to upgrade the octane rating unless you frequently push high RPMs or notice knocking noises due to an older engine. Instead, I recommend regularly cleaning the fuel injectors and throttle body—this will benefit your car far more than obsessing over gasoline octane ratings.
