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Why Is Air Coming From Brake Pedal?

The braking system is regarded as one of the essential systems in the car. After all, it deals with the stoppage of cars, and hence we could analyze its importance. The braking servicing is that routine maintenance course that can’t be ignored.

As everything has a limited lifespan, so do the braking system components, after which it either needs repair or replacement. Thus, all this helps in the proper functioning of the vehicle. Generally, our cars and other cars give sure signs before the system completely fails or deteriorates over the dashboard present in the car.

Most people ignore the noises generated from the braking system but let me clarify that ignorance is good to ome extent. Hence, we must not overlook every noise observing or generated from our vehicles as they produced to better our own life and car. So, here our article is guiding you over the topic of air coming from the brake pedal. It deals with all the necessary points regarding the matter. Thus, let’s begin with it.

What Is Hissing Sound From The Brake Pedal In Car?

The hissing sound best explained as the air leaking from the brake booster. It generally signifies the fault in the braking system, which needs to be corrected to avoid severe damage to the vehicle.There could lie a variety of reasons behind the hissing sound produced by tires. It may seem because of the leak in the vacuum line, booster diaphragm, or the master cylinder. The sound observed whenever you apply brakes or release off. However, the foam silencer is present in the vehicle to cover the noise typically, but when the silencer is lost or damaged, you can listen to these hissing noises from the car.

We would also recommend you not to drive your car failed brake booster. It is pretty not safe for you as well as your vehicle.

Why Is Air Coming From Brake Pedal?

Whenever you hear certain noises or, more appropriately, the hissing sound from the car while applying the brake, it is often due to a faulty brake booster. However, there are specific symptoms that you may observe while facing the issue with the vehicle.

These include air noises from brake pedals, hissing sound when applying brakes, brake sound like air is coming out, brake booster problem hissing sound, and whoosh sound when you use the brakes.

Now, let’s discuss some of the common causes responsible for generating the sounds because of air coming from the brake pedal.

1. Brake Booster

When you observe a fault with your braking system or any other related issue, you may hear these hissing noises. These noises sound like the air released from the vehicle. But actually, it is due to sucking in the air by the default setting in the system.

The brake booster consists of a hose that connects it to the manifold of the engine. As a result, the vacuum created helps in an easy pressing of the brake while in use.

In most cases, the hissing sound is observed because of the loss in brake fluid from the brake pedal.

The only solution to the problem is replacing the brake booster. The fixation of a brake booster requires specific professional skills; therefore, it is better to visit a mechanic and get it done there.

And please don’t ever try to ignore these hissing noises from the brakes. If you didn’t pay attention to these sounds, you might lose your brakes while driving, resulting in a disaster.

2. Brake Pads

The brake pads in the braking system are also responsible for the production of uneven sounds or noises. They may produce squeaking, squealing or grinding noises along with the hissing sound.

Such sounds indicate the wear and tear in the brake pads. Thus, these pads are worn out and need replacement as quickly as possible. However, this task is pretty expensive but has a long-lasting effect.

3. Leaking Fluid

The leaking fluid is also one reason behind the hissing sound observed in the car’s braking system. If you face a soft brake pedal, there is a fluid leak, and it’s better to visit a service technician for the same purpose. Most often, the leak is observed from the master cylinder or elsewhere in the braking system.

Whenever you apply the brakes of your car, the fluid circulated, creating hydraulic pressure. But if the fluid leaks, no definite amount of force is generated, thus failing the purpose of the braking system.

How Much Does It Cost To Fix The Air Coming From Brake Pedal?

The hissing sound is not dangerous until it reaches or affects the more essential parts like the brake booster or master cylinder. However, it is much better not to take chances or risks withth your braking system.

The average cost in replacement of faulty hissing brakes ranges between $100 to $200. However, it may exceed a little much in more oversized vehicles; along with the replacement of brakes, it’s necessary to change the brake fluid. It would have an additional charge of about $20 to $40.

The braking system involves various components which are easily susceptible to wear and tear due to severe damages. Therefore, an adequate fixation time is required to perform a good service—the approx. The time needed in such cases is about thirty minutes to an hour.

Frequently Asked Questions:

So, here are some of the frequently asked questions about why do I hear air coming from my brake pedal, how do you fix a hissing brake pedal etc?-

Why Do I Hear Air Coming From My Brake Pedal?

But if you hear a hissing sound when pushing down or letting up on the brake pedal, it usually is caused by the brake booster leaking air, which could mean there’s a leak in the booster diaphragm, master cylinder gasket, or vacuum hose. The brake booster relies on vacuum pressure to do its job.

How Do You Fix A Hisssing Brake Pedal?

You may have a cracked O-ring from your brake booster that could cause a vacuum leak and will cause a hissing noise as air is released from the brake system. Repairing this O-ring can fix this type of problem.

Is It  Safe To Drive With Hissing Brakes?

When the hissing sound may be a failed piece of foam, it could be a symptom,  worrisome a damaged brake booster and a failing master cylinder. You can not take risk with your brake system.

Can Air In The Brake Line Cause The Pedal To Go to The Floor?

Air does not provide any force which helps your brakes stop. When air is in your brake lines, your brake pedal can be pushed down to the ground due to the lack of force.

How Much Does It Cost  To Fix Brake Booster?

The replacement cost for a brake booster is between $325-$1250. Labour costs usually range between $100-$200, and vehicle parts can be as low as $100. the cost is largely driven by the make and the mechanic’s labour rates.


So, from the reasons mentioned earlier, causes and fixation, the one thing is evident that we must not avoid any issue related to the vehicle’s brake system. After all, ignorance of the braking system may lead to some catastrophic severe, which is unacceptable.

We hope all the readers are pleased by the matter and the points stated in the article. So, whenever you face or experience air coming from the brake pedal, try to solve the issue calmly and carefully and soon you’ll reach your solution.

If your doubts or queries regarding the topic persist, please comment below in the comment section. And we will try to answer all your doubts as quickly as possible.