What impact does high speed driving have on fuel efficiency?

High-speed driving reduces fuel efficiency due to the increased air resistance and drag that vehicles face at higher speeds. As a vehicle accelerates beyond a certain speed, typically around 50-60 miles per hour, the engine has to work harder to overcome these forces, leading to greater fuel consumption. Additionally, at high speeds, the engine operates less efficiently, which further contributes to increased fuel use.

Driving at lower speeds often allows for optimal engine performance and better fuel economy, as the car can maintain a more efficient engine speed and use less fuel for propulsion. Therefore, it's important for drivers to be mindful of their speed not only for safety reasons but also to minimize fuel consumption and reduce overall costs.