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Fading brake pedal

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Old 03-08-2015, 03:26 PM
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Default Fading brake pedal

So my 99 has a soft fading pedal.. We've replaced 2 brake hoses and master cylinder.. Bled it great no air left and bled the abs.. But the abs isn't bleeding.. Is there a way to bypass to have brakes or a way to check it
 
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Old 03-08-2015, 03:45 PM
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The master cylinder must be bench bled before installing. After installing it you will need to gravity bleed the entire system, one wheel at a time. DO NOT pump the pedal. Plan on at least a quart of fluid, and don't let the master run dry during the gravity bleed. Each wheel may take 10 minutes or more to gravity bleed. After all wheels are bled, (with no air bubbles exiting the bleeder), close the bleeder and apply constant pressure on the pedal, then quickly open & close the bleeder. Repeat at each wheel. If this does not cure the problem, you will need to have the automated bleed performed with a capable scan tool. Post your results.
 
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Old 03-08-2015, 03:57 PM
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We bled it all and used scan tool.. Still fading
 
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Old 03-08-2015, 04:09 PM
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Also have a good pedal with it
Off.. Kinda leaning toward something messed up in the abs module
 
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Old 03-08-2015, 04:16 PM
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The automated bleed expels air from the solenoids in the EBCM. The air is forced into the steel lines. The entire system needs to be gravity bled after the automated bleed to remove the air from the lines.


Did you bench bleed the master first? If not, it will continue to push air into the EBCM making your automated bleed a waste of time, and you need to start all over, by bench bleeding the master, then do the automated bleed, then gravity bleed it.
 

Last edited by Captain Hook; 03-08-2015 at 04:38 PM.
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Old 03-09-2015, 05:34 PM
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What is gravity bleed again?
 
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Old 03-09-2015, 05:44 PM
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Post #2 explains. Open one bleeder at a time, and let the fluid run. Same process when you replace a caliper or a line. VERY important NOT to pump the pedal. All it does is create an unnecessary headache.
 
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Old 03-10-2015, 12:34 PM
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We did a pressure
Bleed.. There is no air in the lines
 
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Old 03-10-2015, 12:51 PM
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A pressure bleed will not clear the trapped air from the solenoids in the EBCM.
 
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Old 03-11-2015, 08:18 AM
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So a gravity bleed needs done?
 


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