Hi when i push on my brakes it makes a hissing sound but no braking and then goes firm and brakes if you push hard. Whats wrong ? could there be air in the system cos its been garaged for the last year? fluid level ok in master cylinder. THanks
2007-04-13 18:29:16 · 17 answers · asked by hemal 1 in Cars & Transportation ➔ Maintenance & Repairs
Hissing means your booster diaphram is torn, leaking vacuum. If it works when it warms up, it's a worn seal. The fix is to replace the booster as I don't know of any repairs or kits for them.
2007-04-13 18:36:05 · answer #1 · answered by Anonymous · 1⤊ 0⤋
What you describe sounds like air in the system. Even though it has been sitting for a year, that should not let air in, unless there is a leak some where. Fluid level means very little. What you describe is not an indication of brake pads being worn to much. If there was a grinding sound, then I would agree, but what you say doesn't indicate that. Rust would not cause your symptoms either. While it won't hurt to check the pads for wear, nor the disks for any uneven wear, what you say sounds like air, and the brakes need to be bled to get the air out. As for the vacuum assist which someone else mentioned, since that is a direct connect to the intake manifold, a leak there would cause engine problems which you have not named.
2007-04-13 19:05:00 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Some breaks are vacuum assisted and it sounds like you have a vacuum leak.
Stopping a 2 ton car with human muscle power is a bit of a strain. So if you look at where your master cyclinder is bolted to the car there should be a cyclinder or drum device. This is a vacuum chamber. When you press the pedal you open a vacuum value and you get your engine's assistance in applying power to the hydraulicsystem.
With a vacuum leak (the hiss) you are on pure muscle power, which is why you need to push hard.
Air in the hydraulic lines would not cause a hiss but would make the brakes very mushy. Instead of pushing the brakes pads against the plate, you are compressing the air in the hydraulic lines.
You might just have a $1.00 hose to replace. If your vacuum power assist drum is leaking then that will be fairly major.
2007-04-13 18:44:11 · answer #3 · answered by Craig 1 · 1⤊ 0⤋
The Hissing Sound Is Coming From Your Master Cylinder---
The Diaphragm Is Ruptured----------------------------------------------
The Hard Brake Peddle Is From Air In Lines------------------------
A Lot Of Possibilities With The Cause Of Air In Lines------------
If Not Familiar With Brake Systems --Would Suggest Speaking With A Real Brake Mechanic!!!!!!!!!!!!!!!!!!!!!!!!!!
2007-04-13 18:48:57 · answer #4 · answered by David S 1 · 0⤊ 1⤋
Need more info. The hiss sound could be an air leak, but a metallic hiss could be the wear alarm on your brake pads. Take your car to a brake shop, you might need a new set of brakes and rotors.
The hiss sound is a way to let you know your break pads are wearing ...
Or it could be your brake pads have "cristalized" they are not weared but they make noise when driving.
Anyway you should visit the brake shop.
2007-04-13 18:36:51 · answer #5 · answered by pedrofariaslozano 2 · 0⤊ 2⤋
Brake Master Leakage!!
Check the main brake master it should be located under the brake fluid bottle,and check the 4 wheels.
2007-04-13 20:23:54 · answer #6 · answered by hamed206 2 · 0⤊ 0⤋
If the hissing sound continues when the car is standing still, I think you have a vaccuum leak. If the hissing could be more of a grinding and is only when the car is moving with the brakes applied, then I think they are wore out
2007-04-13 18:38:19 · answer #7 · answered by jimanddottaylor 7 · 0⤊ 1⤋
hissing? or is it grinding? sounds like the time I had a brake pad seperate from the shoe..... will wear out a rotor in no time... you need to inspect the brake pads and rotors....soon... or have it done.... is it all the time or intermitant... after several minutes of use or all the time? Hissing might be the brake fluid boiling... not likely though.... if you had no brakes at all I might say a leak... but yoy would see the fluid dripping on the driveway.
2007-04-13 18:34:42 · answer #8 · answered by curious dad 3 · 0⤊ 2⤋
sounds like theres a leak in or around the vacumm booster
look behind the master cylinder at the big rubber hose going to the booster pump
2007-04-13 18:33:29 · answer #9 · answered by gregs111 6 · 1⤊ 0⤋
Sounds like rust on the rotors? If so, when you first pulled it out you may have worn ruts in the rotors. Take it to a brake shop and ask them to turn the rotors. If the pads are bad they'll let you know that as well.
2007-04-13 18:32:32 · answer #10 · answered by Anonymous · 0⤊ 2⤋