What type of gasoline should a Ford Focus use?
1 Answers
Ford Focus should use 95-octane gasoline, as recommended in the vehicle's official user manual. In addition to checking the appropriate gasoline grade in the user manual, you can also find it indicated on the fuel tank cap of the Ford Focus. Generally, 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. For higher compression ratios, 98-octane gasoline is recommended. However, with the application of new technologies, the compression ratio alone cannot determine the gasoline grade, as high compression ratio engines can also be tuned to use lower-octane gasoline. 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 you occasionally use the wrong gasoline grade in a Ford Focus, simply switch back to the correct grade after the current tank is used up. However, long-term use of the wrong gasoline grade can have the following effects: Using a higher-octane gasoline in a vehicle designed for lower octane will not cause damage, but the increase in octane can alter the fuel's ignition point, leading to delayed combustion in the engine. This results in reduced engine power and thermal efficiency, manifesting as poorer performance. Using a lower-octane gasoline in a vehicle designed for higher octane can cause engine knocking. The significantly lower octane number reduces the gasoline's ignition point, causing it to ignite prematurely during the compression stroke. If the fuel ignites before the spark plug fires during the compression stroke, resistance occurs during the upward stroke. This resistance makes the engine run very unstably. Mild knocking may only increase noise without significant engine damage, but 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.
