Brake problem, what happened??

JB91389

decisions...decisions...
Jun 22, 2006
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Ottawa
So i'm driving around and my brakes are working perfectly. I go to the mall and turn the car off. 15 min later I go to start my car, BTW its an 87 turbo Auto. I go to step on the brakes to put it in reverse and the pedal goes down to the floor. As if I had no brakes. As I let the car warm up, the brakes began to feel normal again. This has never happened before.

What could have happened?
 

bigal0043

New Member
Jun 29, 2005
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Plattsburgh,NY
www.mk3supra.net
i would say probally bad master cylinder, block in the line maybe, air pocket somewhere... is this new problem or recent thing? I know mine did that where i had to pump it to get pressure but that was after i was driving around for say 15mins.. my problem was i had a optional o2 sensor bung on my dp and the bolt had fallen off and exhaust was boiling the brake fluid lol..
 

JB91389

decisions...decisions...
Jun 22, 2006
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Ottawa
This is a new thing, just happened yesterday, Like you did I also pumped the brakes for a bit and then it got back to normal.
 

iwannadie

New Member
Jul 28, 2006
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gilbert, az
i had the same thing, turned out to be the master cylinder went out.

sucked too all the local brake shops wanted a Fortune for labor+parts. ended up getting the MC from napa and had a local small brake shop put it in for like 20 bucks. this was before i turned a wrench in my car, now id take it on myself...
 

IJ.

Grumpy Old Man
Mar 30, 2005
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I come from a land down under
Dead mastercylinder.

For everyone else it's pretty easy to check for this apply light pressure to the pedal if it's bad it will slowly creep to towards the floor as there isn't enough pressure to force the lip seal against the bad surface in the cylinder.

A good master will lock up solid.
 

JB91389

decisions...decisions...
Jun 22, 2006
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Ottawa
When I apply light pressure to the pedal, it does not creep to the floor. My dad just used it this evening and it worked fine.
 

IJ.

Grumpy Old Man
Mar 30, 2005
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Ok next thing it can be is Old fluid, brake fluid is Hygroscopic meaning it attracts water, water when boiled turns to steam, steam compresses and bingo the pedal goes to the floor!
 

iwannadie

New Member
Jul 28, 2006
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gilbert, az
id still bet its the MC. if its going to the floor then later works thats exactly what mine did. it could be slowly dieing thats why its not an all the time problem.

start cheap and bleed the brakes with new fluid and go from there.
 

JB91389

decisions...decisions...
Jun 22, 2006
698
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Ottawa
the brakes were bled and its new fluid...My MC is probably going out....but now my fron drivers caliper seems to be seizing sometimes....it wont release sometimes...time for a new caliper?