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Discussion Starter · #1 ·
I was driving home yesterday and had to brake hard to stop from running a light. The pedal was soft and spongy and I almost rolled into the intersection. Then I started noticing when I applied the brakes, there is a sort of hissing sound coming from the pedal area.

Made it home. I checked the fluid level, full. No leaks any where.
Anyways I bleed all the old fluid and filled with fresh. I also bleed the brakes of air.
That didn't help any, does this mean my brake booster took a dump?

EDIT
I forgot to add that while I was bleeding the brakes, I had my friend manipulating the brake pedal. Each time he pressed on the brake the engine would stutter and would come close to shutting off. This also happened when I took it for a test drive after the bleeding.

Also I was describing it wrong. It is definitely a stiff/hard pedal and not soft like I previously thought.
 

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Sounds more like a hydraulic problem. A bad brake booster makes the pedal hard, not soft.
 

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The booster diaphragm has a hole in it and is causing a vacuum leak when the booster is operated. You are not getting any power assist because the booster is not working and the vacuum leak is stalling the engine.
 

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Buster28 said:
The booster diaphragm has a hole in it and is causing a vacuum leak when the booster is operated. You are not getting any power assist because the booster is not working and the vacuum leak is stalling the engine.
Exactly. Bad booster.
 

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Discussion Starter · #5 ·
Thanks guys.

I got one ordered that should come in on Monday.
Doesn't seem like it's too hard to replace, any tips?
 

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Not hard, just unbolt the master brake cylinder, force it a little bit to the side, carefully. Then go under the dash and take the pin that holds the pedal to the cylinder, and then all four bolts that keeps it in place. To put it back, just the reverse of that
 
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