replacing brake booster

2002 CHEVROLET TRAILBLAZER

167,000 MILES • 6 CYL • 4WD • AUTOMATIC

MS. LISA

MEMBER
2 POSTS

Vehicle has no brakes after changing the brake booster, adding new lines, recap brake fluid, bled, and fairly new master cylinder. The brakes goes right to the floor and you hear air. Can someone help me?

Jul 27, 2019 at 10:06 PM

SCGRANTURISMO

✓Experienced Mechanic
4,897 POSTS

Hello,

This could be a problem with the vacuum hose going to your brake booster or the brake booster check valve. In the diagrams down below I have included a factory diagnostic troubleshooting flowchart for your vehicle's brake assist system as well as instructions for the removal and installation of the vacuum brake boost check valve and hose. Please go through these guides and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

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Feb 24, 2021 at 11:47 AM

MS. LISA

MEMBER
2 POSTS

I will check. thank you

Feb 24, 2021 at 11:47 AM

STRAILER

✓Experienced Mechanic
55,065 POSTS

If I can jump in here. does this car have ABS? if so you may need to have the ABS valve opened using a scan tool while bleeding to get the air out. This guide can help as well:

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

Please run down this guide and report back.

Feb 24, 2021 at 11:47 AM