2002 Tahoe brakes spongy after master cyl replacement

2002 CHEVROLET TAHOE

62,000 MILES • V8 • 4WD • AUTOMATIC

DCDUCKS

MEMBER
1 POST

I have replaced the master cylinder, bench bled and bled the brakes enough to replace all the fluid and remove any air in the system. When the motor is off the brakes are firm and cannot be pushed to the floor. When the motor is started the brakes can be pushed to the floor. There is no sign of leaking fluid and I possibly replaced a good master cylinder since the problem has not gone away. Any suggestions would be greatly appreciated.

Aug 17, 2008 at 4:11 PM

BRIAN 1

✓ASE Certified Mechanic
1,030 POSTS

you have to do an "automated bleed" with a tech 2 scan tool.if you dont you will never get a brake pedal.when you do an automated bleed it pushes all the traped air in the ebcm and the hydralic sys into each caliper and then you can bleed the system.when you put the master cyl on you let air into the sys which got pushed into the ebcm when you bleed the sys. post back with what you find.

Mar 16, 2021 at 10:09 AM

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