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2008 Cobalt brake pedal sinks when going forward, but not in reverse

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Old Nov 1, 2022 | 09:25 PM
  #11  
greg8453's Avatar
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From: Davison MI
Originally Posted by working on it
Since I couldn't reach my vise in the garage (it's surrounded by tons of my wife's collectibles and junk ...same thing, in my mind), I mounted the new MC onto the brake booster, and bled it in place, using a brake bench bleeding kit, before I hooked the lines up.
How much fluid did you run through it after no bubbles? I would have another person tap on it while bleeding. The vibrations will bust up bubbles that are hard to get out.
Old Nov 2, 2022 | 07:37 AM
  #12  
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I meant that it is fully engaged at 3, but impossibly tight at 6!
That doesn't mean the front shoe is engaging. The parking brake engages the rear shoe primarily.
Has anyone "adjusted" the parking brake thinking that adjusted the brakes? People do that.
Old Nov 2, 2022 | 03:34 PM
  #13  
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From: dfw texas
Originally Posted by greg8453
How much fluid did you run through it after no bubbles? I would have another person tap on it while bleeding. The vibrations will bust up bubbles that are hard to get out.
As I stated, we bled the brakes 9 times (3 rounds of 3 attempts, in sequence), using probably 4 quarts of Bosch ESI6-32N Brake Fluid (not cheap), and maybe another 1/2 quart while bench bleeding.

And in reply to don brew, I'm almost certain that the rears were adjusted correctly, as I adjusted the first one, as I had previously done on my HHR. But then, I've been wrong many times before. That's why we had given up, as nothing we did made much difference.
Old Nov 2, 2022 | 04:07 PM
  #14  
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Then it must be Gremlins You didn't feed them after midnight?
Old Nov 2, 2022 | 04:51 PM
  #15  
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Did you tap on the master as you bleed it? No. I'll put my money on air.
Old Nov 2, 2022 | 08:30 PM
  #16  
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I might think air, if it was in both directions. But, it is soft going forward and hard in reverse.
Old Nov 2, 2022 | 08:36 PM
  #17  
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From: Davison MI
Does reverse brake normal?
Old Nov 2, 2022 | 08:42 PM
  #18  
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The original questios was "brakes soft in forward narmal in reverse".. At least that is what I read.
My theory that the rear brakes are to blame was discounted so, the only other thing I can think of is the gremlin theory
Old Nov 3, 2022 | 08:25 AM
  #19  
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The rear brakes are reportedly adjusted but not correctly, the ebrake starts to engage at 3 clicks and fully engages at 6 clicks, should be 3 clicks.
Old Nov 3, 2022 | 11:15 AM
  #20  
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You should adjust the rears until they start to drag.



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