2003 GMC Sonoma Brakes

2003 GMC SONOMA
125,000 MILES • 4.3L • 6 CYL • 4WD • AUTOMATIC
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LASURVIVOR47
  • MEMBER
  • 45 POSTS
Engine off brakes firm. Engine on pedal travels to the floor. I know I have a vacuum leak. OBD2 tested. Thinking it's maybe the booster. Replaced lines from the MC to the ABS pump. Bled system with hand pump. No air in system, and no leaks. Again firm pedal with the engine off, and pedal travels to the floor with the engine on. I let the engine warm up also...Thanks!
Jan 8, 2014 at 8:05 PM
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HMAC300
  • ✓ASE Certified Mechanic
  • 48,601 POSTS
  • ASE Certified Mechanic
have a pro use a scanner to bleed your brakes, it may be air in the abs unit and he can make valves in abs openwhile bleeding, it can take up to 3 qts to get air out of system especially since you have replaced a couple of lines.
Jan 9, 2014 at 6:55 AM
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LASURVIVOR47
  • MEMBER
  • 45 POSTS
Thanks for getting back to me. I will take it to the garage.
Jan 9, 2014 at 10:56 AM
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