CRV, Should Turbocharged Engines Use 92 or 95 Octane Gasoline?
2 Answers
According to the official vehicle manual recommendation, the CRV should use 92 octane gasoline. In addition to checking the appropriate gasoline grade in the vehicle manual, the CRV's recommended fuel type can also be found on the fuel tank cap, which is usually marked there. Typically, 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, the compression ratio alone cannot determine the appropriate gasoline grade. Even engines with high compression ratios can 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, 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 CRV occasionally uses the wrong gasoline grade, simply switch back to the correct grade after the current tank is used up. However, prolonged use of the wrong gasoline grade can have the following effects: For vehicles recommended to use lower octane gasoline, accidentally 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 in practice. For vehicles recommended to use higher octane gasoline, using lower octane gasoline can cause engine knocking. Because the octane number is too low, the reduced ignition point may cause the gasoline to ignite prematurely 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 may only increase noise without obvious damage to the engine. However, noticeable knocking indicates severe engine conditions, where vibrations not only affect driving stability but also cause abnormal wear on pistons and cylinders, potentially leading to cylinder scoring in severe cases.
I've been driving the CR-V turbocharged version for two or three years and always insist on using 95-octane gasoline because the manual clearly recommends it. Turbocharged engines have a high compression ratio, and lower-octane 92-octane fuel can easily cause knocking, which is abnormal combustion. Long-term use may damage the cylinders and pistons, affecting the engine's lifespan. 95-octane fuel burns more stably, improving acceleration response and engine longevity, especially at high RPMs or when climbing hills. Using 92-octane might save a bit of money, but the fuel consumption could also be slightly higher, making it not worth the trade-off. It's recommended that owners regularly check the user manual or confirm requirements at a 4S dealership to develop the habit of using the correct fuel. The difference is less noticeable in city driving, but 95-octane has significant advantages on highways or long-distance trips. Remember, good fuel protects the engine and gives you peace of mind while driving.
