What type of fuel should a Mercedes-Benz E300 use?

[LeLayla]

The Mercedes-Benz E300 should use 95-octane gasoline, as recommended in the vehicle's official user manual. In addition to checking the appropriate fuel grade in the user manual, you can also find this information on the fuel tank cap, where it is usually indicated. 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. If the compression ratio is even higher, 98-octane gasoline is recommended. However, with the use of new technologies, the compression ratio alone cannot determine the appropriate fuel grade, as high-compression engines can also be tuned to use lower-octane fuel. Other factors, such as ignition timing, turbocharging technology, and Atkinson cycle technology, also play a role. Generally, the higher the fuel grade, the higher the octane rating 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 Mercedes-Benz E300 occasionally uses the wrong fuel grade, simply switching back to the correct grade after consumption is sufficient. However, prolonged use of the wrong fuel grade can have the following effects: For vehicles designed for lower-octane fuel, using a higher-octane fuel will not cause damage, but the increased octane rating may alter the fuel's ignition point, leading to delayed combustion. This can reduce the engine's power output and thermal efficiency, resulting in poorer performance. For vehicles designed for higher-octane fuel, using a lower-octane fuel 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 will arise during the upward stroke. This resistance can make the engine run very unstably. Mild knocking may only increase noise without noticeable engine damage, but severe knocking indicates serious engine issues, affecting not only driving stability but also causing abnormal wear on the pistons and cylinders, potentially leading to severe engine damage.