Using 95 octane fuel in a Lynk & Co can be awkward, as the manufacturer recommends 92 octane gasoline in the official vehicle manual. In addition to checking the appropriate fuel grade in the vehicle manual, Lynk & Co owners can also find this information on the fuel tank cap, which is clearly marked. Typically, the fuel grade can also be determined based on the engine's compression ratio. Vehicles with a 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 advent of new technologies, the compression ratio alone is no longer the sole determinant of the appropriate fuel grade. High-compression engines can also be tuned to use lower-octane fuel, as factors like ignition timing, turbocharging technology, and Atkinson cycle technology also play a role. Generally, higher-octane gasoline has a higher octane rating and better anti-knock properties. For example, 92 octane gasoline contains 92% isooctane and 8% n-heptane, while 95 octane gasoline contains 95% isooctane and 5% n-heptane. If a Lynk & Co occasionally uses the wrong fuel grade, simply switching back to the correct grade after the tank is empty is sufficient. However, prolonged use of the wrong fuel grade can have the following effects: For vehicles designed for lower-octane fuel, using higher-octane gasoline won't cause damage, but the increased octane rating can alter the fuel's ignition point, leading to delayed combustion in the engine. This reduces the engine's power output and thermal efficiency, resulting in poorer performance. For vehicles designed for higher-octane fuel, using lower-octane gasoline can cause engine knocking. The significantly lower octane rating lowers the fuel's ignition point, causing premature ignition during the compression stroke. If combustion occurs before the spark plug fires, resistance is created during the upward stroke. This resistance makes the engine run very unstably. Mild knocking may only increase noise without noticeable engine damage, but severe knocking indicates serious engine issues, affecting driving stability and causing abnormal wear on pistons and cylinders, potentially leading to cylinder scoring.
