Can the Highlander use both 92 and 95 gasoline randomly?
3 Answers
No, it cannot be used randomly. The Highlander should use 92 gasoline, as clearly indicated on the fuel tank cap and in the vehicle manual. The differences between 92 and 95 gasoline: 1. Different octane values: The difference between 92 and 95 gasoline lies in their octane values. 92 gasoline has an octane value of 92, while 95 gasoline consists of 95% isooctane and 3% n-heptane. 2. Different carbon deposit amounts: The same quantity of 92 and 95 gasoline will produce slightly different amounts of carbon deposits, but the difference is minimal. 3. Different prices: Due to the different octane values, 95 gasoline, with its higher octane value, is more expensive than 92 gasoline. 4. Different anti-knock properties: Gasoline grades are classified by octane value. For example, 97 gasoline refers to a fuel with anti-knock properties equivalent to a mixture of 97% isooctane and 3% n-heptane. The higher the grade, the better the anti-knock performance. The choice of gasoline grade should be based on the engine's compression ratio.
Last time I drove the Highlander to Tibet for a self-driving tour, I finally figured out the refueling situation. The owner's manual clearly states 'recommended 92 unleaded gasoline,' and there's also a label inside the fuel tank cap. The 2.0T engine is specifically tuned for 92 octane with a compression ratio of 9.6:1 - using higher octane is just a waste of money. Once at a high-altitude gas station, I had to use 95 octane, and there was absolutely no difference in performance, but fuel consumption increased by 0.3 liters. However, a mechanic told me that long-term mixed fueling would cause the ECU to frequently adjust the ignition timing, leading to carbon buildup. The most cost-effective approach is to consistently use 92 octane, unless you're in remote areas where 92 isn't available - temporarily using two tanks of 95 octane for emergencies isn't a big problem.
After three years of driving the Highlander, I've experimented with three fueling strategies: exclusively using 95 octane in the first year, mixing fuels in the second year, and sticking to 92 octane in the third year. Real-world testing showed 95 octane costs 8 cents more per kilometer without noticeable power gains. The manufacturer's technical documentation states TNGA platform engines have knock sensors compatible with 92-95 octane. However, a dealership technician revealed a crucial detail - mixed fueling causes the sensor to constantly adjust ignition timing, increasing piston ring wear by 17%. Once after refueling with 95 octane for mountain driving, the check engine light came on, with diagnostics showing fuel adaptation issues. Now I consistently use Sinopec's 92 octane, saving ¥40 per tank - enough for a hotpot meal.
