A car uses more fuel under hard acceleration. So don’t race up to red lights or stop signs, avoid quick “jackrabbit” starts, and don’t goose the throttle to jump into holes in traffic. Avoid high speeds on the highway. As your speed increases, the aerodynamic drag increases in exponential fashion, so the engine has to work harder – and use more fuel – to maintain your speed and move the car through the atmosphere. Driving 62 mph instead of 75 mph can reduce fuel consumption by as much as 15%.