air coming out of the brake lines... that is if its a truck. if you aply the parking brake.
it is hissing because there is a vacume leak in the brake booster it will require a new brake booster
Sounds like the power brake booster is bad. Get it checked out.
Hissing from the brake pedals being push indicates that there is air in the brake system. It also indicates that the brake pads may be wore down and are not able to grab to stop the car.
Common causes of mechanical breaks in a vehicle's braking system include worn brake pads, damaged brake rotors, leaking brake fluid, and malfunctioning brake calipers. Regular maintenance and inspections can help prevent these issues.
Brake dust!
Sounds like are running "metal to metal" . Brake linings need to be replaced ==== Another thing that can cause hissing too is if your vacuum assist has a vacuum leak in it. As you apply pressure it it is forcing air out of this leak. This can sometimes be heard inside the vehicle if it is big enough. It usually causes you to have to use more force on the pedal to stop also.
Faulty Vacuum Brake Booster.
While the vehicle is stopped, the brake system should be tested by checking the parking brake (also known as the handbrake) to ensure it holds the vehicle in place when engaged. Additionally, the brake pedal can be pressed to assess the firmness and responsiveness, indicating the condition of the hydraulic system. If equipped, testing the anti-lock braking system (ABS) warning light should also be done to ensure it functions correctly. Finally, a visual inspection of the brake pads and discs for wear can be beneficial.
An engine brake, also known as a compression brake or Jake brake, is a system in a vehicle that helps slow down the vehicle by using the engine's compression to create resistance. When activated, the engine brake closes off the engine's intake valves, which restricts the flow of air into the cylinders. This causes the engine to work against itself, slowing down the vehicle without using the vehicle's brakes.
Maybe, depends on vehicle - and you haven't shared that with us.
When a driver applies the brakes, the vehicle experiences deceleration due to the friction between the brake pads and the brake rotors. This rapid slowing down shifts the weight of the vehicle forward, causing any unsecured objects or passengers to slide in the same direction. Additionally, the inertia of these objects causes them to continue moving forward until they are stopped by a seatbelt or other restraint.
By the hissing noise it sounds like you need a new brake booster