Is it allowed to coast downhill in a small car with the engine off?

[McJace]

Driving a small car downhill with the engine off is not allowed, as this operation poses significant safety hazards. Consequences of coasting with the engine off: Coasting with the engine off will result in the loss of brake assistance and engine braking force, relying solely on the friction between the brake pads and discs for braking. This can easily cause the brake pads to overheat, leading to a loss of braking effectiveness. Additionally, the power steering pump will also fail, rendering the steering wheel uncontrollable, creating a dangerous situation with neither steering nor braking. Correct method for descending steep slopes: When descending steep slopes, use engine braking. For manual transmission cars, shift into 1st or 2nd gear, and for automatic transmission cars, shift to L gear. Avoid prolonged braking.

[MacEvelyn]

Having driven for decades, my experience tells me that coasting downhill with the engine off is a major taboo. Once the engine is turned off, the brake booster loses power, making the brakes heavy and unresponsive. On steep slopes, gravity rapidly increases the vehicle's speed, significantly raising the risk of brake failure. I've seen cases where people tried to save fuel this way, only to lose control and cause accidents. The correct approach is to shift into a lower gear, such as 2nd or 3rd, allowing the engine to help control the speed for a safe descent. It's crucial to develop good driving habits—never risk lives to save a few bucks. Ensuring your safety and that of others is what truly matters.

[VanLilah]

Driving a small car downhill with the engine off and coasting is absolutely not advisable due to poor safety. When the engine is off, the brake booster stops working, requiring more force to brake effectively; meanwhile, the power steering system may fail, making the steering wheel heavier. The speed of downhill coasting is rapid, and in case of sharp turns or obstacles, there's simply no time to react. Many countries' regulations explicitly prohibit this practice to prevent accidents. I recommend always keeping the engine running and using engine braking techniques. From a vehicle maintenance perspective, it's also crucial to regularly check the braking system to ensure safe and secure travel every time.

[Keegan]

As an ordinary car owner, I strongly advise against this practice. Coasting downhill with the engine off may seem fuel-efficient, but it poses significant risks. When the engine stops, the brake booster fails, making the brakes stiff and steering difficult. In an emergency, controlling the vehicle becomes nearly impossible. I once heard a friend share a similar experience that nearly ended in disaster. When driving downhill, you should shift to a lower gear and rely on engine braking to control your speed. Remember, safety comes first! Regularly maintain your braking system to ensure stable stopping in any road condition.

[StBethany]

I think this action is too risky. After the engine stalls, the brake system loses power assist, requiring more force on the brake pedal to be effective. On steep slopes, the vehicle accelerates quickly, and in case of emergency braking, it might be too late. Additionally, power steering may also fail. From a practical perspective, some people have tried this to save effort or money, resulting in runaway vehicle accidents. The correct approach is to keep the engine running and use the transmission's low gear (such as L gear or manual mode) to control the descent speed. In daily driving, it's important to learn safety techniques and avoid taking such risks.

[AylaFitz]

From an automotive engineering perspective, coasting downhill with the engine off is highly unsafe. When the engine is shut down, the brake booster stops providing vacuum assist, significantly reducing braking power. The power steering system is also compromised. Under steep downhill gravity acceleration, vehicle speed increases rapidly, extending braking distances and raising accident risks. I recommend using engine braking instead: shift to a lower gear to increase engine RPM, which helps slow the vehicle. Always consult your owner's manual - all manufacturers explicitly prohibit engine-off coasting. Develop safe habits like reducing speed before descending and maintaining full control throughout the descent.