Why can't I step on the first brake after the car starts in winter?

It has something to do with stepping on the brakes before the flameout. The braking system of a car can only play its greatest role when the engine is working, and the brake booster pump is the driving force of vehicle braking, and the force we step on the pedal is amplified through it. When the engine is turned off, the brake booster pump will stop. Generally, pressing the brake pedal three times will use up the remaining vacuum force.

So the brakes are hard, but you don't need its help. In this case, just restart the engine, and then try to press the brake pedal hard to restart. After the engine works, the brake booster pump can work again and the natural brake pedal will return to normal.

If you don't step on the brake pedal after the car is turned off, or you find it difficult to step on the brake pedal while driving, it is probably caused by the failure of the brake booster pump. It may be caused by air leakage or blockage of the vacuum tube of the brake booster pump. In view of this situation, if this situation is found before driving, it is safe not to continue driving.

It is better to send it directly to the repair shop for maintenance; If you find it while driving, don't panic. The first thing to do is to slow down and stop. You can try stepping on the pedal several times to see if you can resume braking. When you step hard, you can generally exert your braking force.