Brake pedal is spongy (all the way down when engine is running)?

2008 MERCURY MARINER
160,000 MILES • 2.3L • 4 CYL • 2WD • AUTOMATIC
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ELIESER PEñA REYES
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I replaced the calipers and bled the brakes, the car brakes well when I press the pedal two times. But if I wait a few seconds, the pedal goes all the way down. With the car running.
The ABS pump was working fine before replacing the calipers.
Oct 30, 2022 at 8:21 PM
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SQM
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Hello,

This vehicle does require a scan tool to properly bleed the ABS.
The scanner allows you to open the ABS valves and have a proper bleeding process.


Here is a helpful guide:

https://www.2carpros.com/articles/how-to-bleed-or-flush-a-car-brake-system

I have attached the procedure below for your reference.

Let me know if you have any questions.
Thank you.
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Oct 30, 2022 at 9:20 PM
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ELIESER PEñA REYES
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We already use the scanner to run an OBDII controlled bleeding process. I've already did it two times, and it's still not working properly.
Is it possible that the HCU is damaged? Somehow the pressure releasing valve went all the way always open?
Oct 30, 2022 at 9:38 PM
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SQM
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Are you getting any ABS error codes? Typically is the module is bad it will throw code.
Nov 1, 2022 at 10:25 PM
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ELIESER PEñA REYES
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No error codes. Looks like the HCU. Replaced the ABS HCU and is working fine now.
Nov 2, 2022 at 4:30 AM
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SQM
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So, you were able to fix it. That is great news.
Thank you for updating us.
Nov 4, 2022 at 5:47 PM