Can the Tharu use 92 octane gasoline?
2 Answers
According to the official vehicle user manual recommendation, the Tharu should use 95 octane gasoline. In addition to checking the suitable gasoline grade in the vehicle user manual, the Tharu's recommended fuel type can also be found on the fuel tank cap, which will be clearly marked. Generally, the fuel 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 nowadays, the fuel grade cannot be solely determined by the compression ratio. A high compression ratio engine can also be tuned to use lower octane gasoline. This is because, apart from the compression ratio, other factors such as ignition timing, turbocharging technology, and Atkinson cycle technology also play a role. Generally speaking, 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 Tharu occasionally uses the wrong gasoline grade, simply switch back to the correct grade after consumption. However, long-term use of the wrong gasoline grade may have the following effects: For vehicles recommended to use lower octane gasoline, using higher octane gasoline will not cause damage, but the increase in octane number will alter the fuel's ignition point, leading to delayed combustion in the engine. This means both the engine's power output and thermal efficiency will decrease, resulting in poorer performance as experienced by the driver. For vehicles recommended to use higher octane gasoline, using lower octane gasoline may cause engine knocking. Due to the significantly lower octane number, the gasoline's ignition point is reduced, causing premature ignition during the compression stroke. If combustion occurs before the spark plug ignites during the compression stroke, resistance will arise during the upward stroke. This resistance can make the engine run very unstably. If the knocking is imperceptible, it may only increase noise without obvious damage to the engine. However, noticeable knocking indicates severe engine conditions, where the vibrations not only affect driving stability but can also cause abnormal wear on the pistons and cylinders, and in severe cases, even cylinder scoring.
I see that the Tharu can use 92-octane gasoline, but you need to pay attention to the actual performance. I've been driving the Tharu for several years, and in some small cities in the north, 92-octane fuel is common. I've noticed that the power feels slightly weaker, especially when climbing hills—the throttle response is a bit delayed. This might be because the engine has a high compression ratio, and lower-octane fuel can cause slight knocking. In the long run, engine carbon buildup may increase, potentially leading to higher maintenance costs. However, for daily commuting to save some money, it's acceptable, especially when fuel prices fluctuate—you can save nearly 100 yuan per tank. I recommend checking the dashboard for any warning lights after filling up with 92-octane or testing acceleration smoothness on a highway run. Overall, it's not a big issue, but it's best to confirm the recommended fuel grade in the user manual. Actually, mixing fuel grades doesn’t have much impact; the key is to maintain consistent fuel sources to reduce impurities. During regular maintenance, have a mechanic check the spark plugs to identify any issues promptly.