Something's wrong with my brakes. Help?

  • Thread starter Newai
  • Start date
  • #26
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I've been looking at some articles and videos on vacuum boosters. Seems to fit my situation. I didn't know what a vacuum booster was till dlgoff described it. I just took my car out and noticed that the brake pedal slowly goes all the way to the floor while hissing.

Alright. Thanks everyone! I'll get on that in the next week or two and let you know how it turned out.
 
  • #27
brewnog
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I wouldn't worry. There are plenty of other things (besides your brakes) which can stop you.
 
  • #28
BobG
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I wouldn't worry. There are plenty of other things (besides your brakes) which can stop you.

Turning off your ignition isn't one of them. That usually just locks up the steering wheel and eliminates any pressure your brakes might have possibly found.

I wouldn't drive down any mountains, if I were you.

Pikes Peak crash survivor

You're supposed to use a lower gear when driving down Pikes Peak, but, every few years or so, some flatlander rides their brakes until the fluid all boils away and then they get to test how well they make decisions in an emergency. Most try to choose a good location to crash, but even that doesn't help them if they've allowed themselves to build up too much speed. (By the way, the story is wrong about the cause of the accident. The passenger turned the ignition off and eyewitness reported the car rolling silently down the mountain with the terrified passengers crying while peering desperately out the windows.)

The strangest Pikes Peak accident happened last summer. Engineers sent a driverless Audi up the mountain, using GPS to navigate all of the turns. The car made it fine, but the helicopter filming the car crashed at the summit. Four People Survive Helicopter Crash On Pikes Peak
 
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  • #29
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Newai - Best of luck to you! I hope that is the problem, and that it will be over and your brakes work properly.

Also, I want to suggest again... If this is a friend or family, never mind. But if your mechanic is Joe Schmoe down the road at ABC Automechanic, and you are being billed normal rates, I would strongly suggest thinking about my first sentence in this thread again...... A good mechanic worth the standard billing rate shouldn't leave you asking for suggestions on a physics forum....... No response to me needed.

Again, best of luck.
 
  • #30
DaveC426913
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I wouldn't worry. There are plenty of other things (besides your brakes) which can stop you.

Turning off your ignition isn't one of them.

I was thinking he meant such things as other cars, telephone poles, bridge abutments...
 
  • #31
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What you are hearing is the power/boost(assist) vacuum leaking. It's what the master cylinder is attached to. Between your foot and the master cylinder.

http://www.cardone.com/English/Club/Products/Brakes/Protech/Images/930393e.gif

This would have been my first guess as well...but that doesn't explain the e-brake not working well.

Unless one came before the other? Or they both happened at the same time, but that is a bit unlikely.

I may have missed this, but did they both happen at the same time? Or was the e-brake like that before and maybe you didn't notice because the rest of the brakes were working fine?
 
  • #32
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This would have been my first guess as well...but that doesn't explain the e-brake not working well.

Unless one came before the other? Or they both happened at the same time, but that is a bit unlikely.

I may have missed this, but did they both happen at the same time? Or was the e-brake like that before and maybe you didn't notice because the rest of the brakes were working fine?

I've had the car for about four years. They have both always been like that the whole time I've had it.
 
  • #33
dlgoff
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This would have been my first guess as well...but that doesn't explain the e-brake not working well.

I've had the car for about four years. They have both always been like that the whole time I've had it.

Well, most emergency brakes I've seen only apply to the rear wheels. And they aren't really meant to stop your car like the hydraulic system is designed to.
 
  • #34
turbo
Gold Member
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Well, most emergency brakes I've seen only apply to the rear wheels. And they aren't really meant to stop your car like the hydraulic system is designed to.
Yep! Maybe I'm really used to older vehicles, but most emergency brakes in my trucks/cars were cable-operated tensioners that engaged the rear brakes mechanically. Not really enough to stop you if your vehicle has any momentum, but enough to stall out your engine if you dump the clutch with the EB engaged.
 
  • #35
AlephZero
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I've had the car for about four years. They have both always been like that the whole time I've had it.

Doesn't the US have any mandatory safety inspections, like the UK "MOT test". The name is an anachronism now, because the Ministry of Transport doesn't run they system any more - it's an annual inspection of the safety related components for all vehicles, starting at 3 years old.

You wouldn't be able to tax or insure a car more than 3 years old with faults like that in the UK, and if it was picked up by a numberplate recognition camera while being driven untaxed/uninsured you would probably get a visit from the police not long afterwards.
 
  • #36
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Well, it's been fully inspected at three different places so far.
 
  • #37
lisab
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Well, it's been fully inspected at three different places so far.

Have you had your leg inspected?
 
  • #38
27
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Have you had your leg inspected?

Only my head per the demand of several coworkers. I don't have any cats around handy, so the leg inspection will have to wait.
 

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