Is There Any Harm to a Car If It Doesn't Run on Highways for a Long Time?

[ArcherMarie]

There is no harm to a car if it doesn't run on highways for a long time, as long as it is not driven at low speeds for extended periods. Normal usage is sufficient, but occasionally driving on highways can have certain benefits. Running on highways helps remove carbon deposits: When the engine operates at high speeds, the fuel supply increases, and the fuel flow rate also rises, which helps flush out dirt and impurities in the fuel system, achieving a cleaning effect. Additionally, due to the high-speed movement of the pistons, the temperature inside the cylinders becomes higher, and the flow and speed of air entering and exiting the valves increase, leading to more complete combustion. This helps remove carbon deposits from the valves, making clogged passages smoother.