Why can't the brake be pressed down and the Kia K3 fails to start?

[ElianaAnn]

After braking and stopping, the brake pedal becomes hard and lacks vacuum after being pressed multiple times, making it difficult to press down. Below is some relevant information about the Kia K3: 1. Introduction: As a joint venture brand of Kia in China, Dongfeng Yueda Kia is about to launch the K3, which will become the third K-series model introduced by Dongfeng Yueda Kia. The K3 will debut at the Chengdu Auto Show and features the same powertrain as the Hyundai Elantra. 2. Model: The wheelbase remains the same as the Elantra at 2700mm, providing more interior space for passengers. The Dongfeng Yueda Kia K3 shares the same platform design as the Hyundai Elantra.