Saturn L300 Hissing noise when brake pedal is depressed Inspection at your home or office.

Our certified mobile mechanics come to you 7 days a week between 7 AM and 9 PM.

Estimate price near me

Service Location

Customer Ratings

(42)

How A Diagnostic Works

Instantly book a certified mobile mechanic to come to you

Mechanic diagnoses the problem and quotes necessary repairs

Your vehicle is ready to go

Fair, upfront & transparent pricing for all services

Our certified mobile mechanics can come to you now.

Customer Ratings

(42)

Hissing noise when brake pedal is depressed Inspection Service

How much does a Hissing noise when brake pedal is depressed Inspection cost?

On average, the cost for a Saturn L300 Hissing noise when brake pedal is depressed Inspection is $95 with $0 for parts and $95 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
2002 Saturn L300V6-3.0LService typeHissing noise when brake pedal is depressed InspectionEstimate$114.99Shop/Dealer Price$124.99 - $132.49
2003 Saturn L300V6-3.0LService typeHissing noise when brake pedal is depressed InspectionEstimate$94.99Shop/Dealer Price$105.01 - $112.52
2005 Saturn L300V6-3.0LService typeHissing noise when brake pedal is depressed InspectionEstimate$94.99Shop/Dealer Price$105.01 - $112.52
2001 Saturn L300V6-3.0LService typeHissing noise when brake pedal is depressed InspectionEstimate$94.99Shop/Dealer Price$104.99 - $112.48
2004 Saturn L300L4-2.2LService typeHissing noise when brake pedal is depressed InspectionEstimate$94.99Shop/Dealer Price$105.02 - $112.55
2004 Saturn L300V6-3.0LService typeHissing noise when brake pedal is depressed InspectionEstimate$94.99Shop/Dealer Price$105.01 - $112.52
Show example Saturn L300 Hissing noise when brake pedal is depressed Inspection prices

Brakes are the most important safety components on your vehicle. Despite that importance, it’s easy to take them for granted, at least until your car begins to do strange things. Ordinarily, pressing your brake pedal should result in only the car slowing down or stopping. If you hear a hissing noise when the brake pedal is depressed, it may mean there’s something that needs to be repaired in the system.

How this system works:

On many cars, the master cylinder works in tandem with a brake booster. The brake booster is mounted to the firewall, generally in front of the steering wheel position, and the master cylinder attaches to it. The entire point of the brake booster is to make it easier to press the brake pedal and slow or stop the car.

Your brake booster works on vacuum pressure. There’s a diaphragm inside that is responsible for maintaining pressure when you’re not pressing the pedal. However, when you do press the pedal, a push rod moves forward within the booster and into the master cylinder. The side of the diaphragm facing the cabin vents to atmospheric pressure, while vacuum is maintained on the other side.

This then equalizes with pressure on the other side of the diaphragm, providing the boost needed to make pressing your brake pedal easier. The hissing noise you hear when the brake pedal is depressed could be nothing more than ordinary operation, or it could be a sign of a deeper problem. There are a couple of different potential issues here, some more severe than others.

Common reasons for this to happen:

  • Leaking Vacuum Line: Your brake booster is supplied with vacuum from the engine via a vacuum hose. It’s usually located near the firewall. If this hose has a leak, it can be heard within the cabin.

  • Leaking Brake Booster Diaphragm: The diaphragm that’s responsible for maintaining pressure within the brake booster can fail, particularly if the master cylinder is leaking fluid into the booster. When this happens, you’ll hear a hissing sound when depressing the brake pedal, but the pedal itself will be much, much harder.

  • Damaged or Missing Foam Silence: Most cars equipped with brake boosters also have a foam silencer that’s designed to help prevent you from hearing that hissing sound. If the silencer has degraded or been damaged, you’ll hear the hissing sound.

  • Failing Master Cylinder: If you hear a hissing sound and suspect that the problem is the diaphragm in the booster, the actual cause is likely the master cylinder beginning to fail. Signs that the master cylinder is leaking into the brake booster include low fluid in the reservoir with no visible leaks.

What to expect:

A top-rated mobile mechanic will come to your home or office to inspect your brake system, including the brake pedal operation, the brake booster and listen to the hissing sound. The mechanic will then provide a detailed inspection report that includes the scope and cost of the necessary repairs.

How it's done:

The mechanic will need to crank the car in order to verify the hissing sound, and a test drive may be necessary to duplicate the complaint. Additionally, the mechanic will inspect the brake pedal operation, the condition of the brake booster, the master cylinder, the level of fluid in your system and more.

How important is this service?

Power brakes are wonderful things, making it far easier to work a brake pedal that would otherwise require significant force to activate. While the hissing sound may be a sign of nothing more dangerous than a failed piece of foam, it could be a symptom of something much more worrisome – a damaged brake booster and a failing master cylinder. You cannot afford to take chances with your brake system. One of our professional mechanics can inspect the entire system and determine if there’s cause for concern, and what needs to be done if there is a problem.

Fast and easy service at your home or office

Backed by 12-month, 12.000-mile guarantee


Meet some of our expert Saturn mechanics

Real customer reviews from Saturn owners like you.

Excellent Rating

(42)

Rating Summary
41
0
0
0
1
41
0
0
0
1

James

11 years of experience
43 reviews
James
11 years of experience
Saturn L300 V6-3.0L - Car is not starting - Pasadena, Maryland
James came earlier than what he was supposed to just to make sure he can check my car throughly to get the proper diagnosis. All the information he gave me in regards to my car was very informative and he was very sweet. Couldn’t have asked for a better mechanic

David

16 years of experience
636 reviews
David
16 years of experience
Saturn L300 V6-3.0L - Oil Pressure Sensor - Fairfield, California
David has worked on my Saturn at least 3 times and I'm always very happy with his work..!!

Pete

16 years of experience
192 reviews
Pete
16 years of experience
Saturn L300 V6-3.0L - Timing Belt - Chula Vista, California
Very good!

Robert

36 years of experience
50 reviews
Robert
36 years of experience
Saturn L300 V6-3.0L - Brake Pads Replacement (Rear) - Concord, California
Robert is a good guy, A very knowledgeable no non-sense mechanic that will do excellent work and won't try to upsell you on useless "maintenance" like typical dealerships try to do.

Excellent Rating

(42)

Rating Summary
41
0
0
0
1
41
0
0
0
1
Number of Saturn L300 services completed
462+
services done by our mechanics
TOTAL NUMBER OF EXPERT Saturn MECHANICS
700+
experts on our platform

Recent articles & questions

How Does Traction Control Work?
Traction control is a car safety feature that prevents wheels from spinning on low-grip surfaces. Electric sensors in your car make the system work.
Lexus Certified Pre-Owned (CPO) Car Program
Drivers Drivers who are in the market for a used Lexus vehicle may want to check out cars under their certified pre-owned program. Many manufacturers have a certified pre-owned (CPO) program, and each one is set up differently. Read on...
Veteran and Military Driver Laws and Benefits in Washington
Drivers Drivers in Washington who are active duty members of the military, as well as veterans, will want to learn more about some of the basic benefits and driver laws in the state and how they will apply. Driver’s license...

Squeaking when you hit a bump in the road

You should check the sway bar bushings (https://www.yourmechanic.com/parts/sway-bar-bushing) and links (https://www.yourmechanic.com/parts/sway-bar-link). You can do so by having someone bounce the car up and down and have the other person feel them by hand. You will be able to feel squeaking...

VSC came on after changing spark plugs oil and air filter on my is 250 lexus

Hello, thank you for writing in. There are several reasons why the traction control and check engine light might come on. There should not be a direct relation between the oil change and the warning lights. The spark plugs may...

High rpm at low speeds first 5-10 minutes of driving

There are some engine controls that affect transmission shift points, such as the throttle position sensor. Those have to be ruled out. If it does turn out to be a transmission issue, check the fluid level and condition. Beyond simple...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (844) 997-3624 · hi@yourmechanic.com