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Weird brake pedal feeling

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Old 02-27-19, 01:22 PM
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abaitedcat
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Default Weird brake pedal feeling

2015 is 250 50,000 miles. I bought it at 44k

1. If my car is off and I pump or step on the brake pedal a few times, each time it gets harder and harder to the point where it wont go down at all after 6 or so pumps. Then when I start the car its softens again and goes down. Is this normal?

2. How will I know when the brake fluid needs replacing? My brake pads seem to be ok and dont make any noises yet so I figured I would do both at the same time, however I'm noticing that when I come to a complete stop, the brake pedal is still able to be pressed down a little bit more and sink down a tad bit. It's not hitting the very bottom or the floor or anything, but it just seems a little bit mushy at a stop. Does this seem normal or are the brakes supposed to just stop rock hard?
Old 02-28-19, 07:38 PM
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Flash5
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Both things are normal. When your car is off and you are pressing the brake pedal like that you're pressurizing the brake fluid so it just gets harder and when you turn the car on the brake master cylinder, etc kicks in thus going back to normal (it's not good practice to pressurize your brake system like that while it's off). To answer your second question, that is normal too. It's never going to be pedal to the floor to get full braking unless you're trying to engage the ABS if in motion lol.
Old 02-28-19, 08:26 PM
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abaitedcat
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Thank you.

my pedal isn't to the floor, but when I press down on it enough to completely brake and keep the car still, i can still kind of push the pedal down beyond that point. Is that normal? Or is there a point when it can no longer go down and it's hard. Mine feels like I can keep going beyond the stopping point a bit... therefore it feels a bit soft.

Could this be a sign of worn brake fluids or do i need to ignore the indicator light at 50,000 miles?

When brake pads wear, am I going to hear them?
Old 03-01-19, 04:40 AM
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mexicanzer
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Your brake pedal is assisted by an engine vacuum booster.
When running the engine supplies vacuum to the booster (negative pressure) when you hit the brakes the opposite side of the booster opens up allowing atmospheric pressure (positive pressure) to enter. In between these 2 chambers there's a diaphragm. When there's vacuum on one side and positive pressure on the other the positive pressure pushes towards the side with vacuum. This helps you push down the brake pedal much much harder than your leg alone can.
When you shut the engine off the is no longer vacuum being supplied to the booster, however it stores enough vacuum in it for a couple of brake applications in the event the engine stalls while driving. If you hit the brakes a couple times you use up this vacuum so the pedal will get hard.
When sitting still with the engine running if you apply substantial pressure it is normal for the pedal to go almost to the floor, with some cars it will go to the floor. When driving it should be nowhere near the floor during normal braking.

Typically brake fluid should be changed every 2-3 years. I've seen 20 year old vehicles with original brake fluid, it was disgusting... And expensive.
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Old 03-01-19, 02:28 PM
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Originally Posted by abaitedcat
Thank you.

my pedal isn't to the floor, but when I press down on it enough to completely brake and keep the car still, i can still kind of push the pedal down beyond that point. Is that normal? Or is there a point when it can no longer go down and it's hard. Mine feels like I can keep going beyond the stopping point a bit... therefore it feels a bit soft.

Could this be a sign of worn brake fluids or do i need to ignore the indicator light at 50,000 miles?

When brake pads wear, am I going to hear them?
You shouldn't ever need to press your brake pedal all the way down, in fact if you had to press your brake pedal ALL the way to the floor to fully stop, then you'd have a problem. Even if you change the brake fluid, it will be about the same. The whole point of changing the brake fluid is to keep the parts in good condition by not getting a lot of contimination in the lines etc. If your pads are worn you WILL hear them squealing haha.
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