Go Back   Honda-Tech > Honda and Acura Model-Specific Technical Forums > Honda Civic (2001 - 2005)
Sign in using an external account
Register Forgot Password?
Search


Welcome to Honda-Tech!
Welcome to Honda-Tech.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the Honda-Tech community today!


Reply
 
 
 
submit to reddit
 
Thread Tools Search this Thread
Old 01-18-2012, 01:31 PM   #1
Whatislove
Honda-Tech Member
Garage is empty, add now
 
Join Date: Aug 2008
Posts: 566
iTrader Rating: (0)
Default Bad brake booster?

How do I test if I have a leaky/bad brake booster? My brake pedal has recently been going from stiff to soft. I dont have any leaks, master is fine and I just did a complete flush and bleed thinking it was some air.

Last edited by Whatislove; 01-19-2012 at 12:31 PM.
Whatislove is offline   Reply With Quote
Old 01-24-2012, 03:40 PM   #2
It Wasn't Me
2014 Ubermobil S
 
Join Date: Oct 2007
Posts: 6,600
iTrader Rating: (0)
Default Re: Bad brake booster?

Functional Test

1. With the engine off, press the brake pedal several times to deplete the vacuum reservoir, then firmly press-and-hold the brake pedal for 15 seconds. If the brake pedal sinks, either the MC is internally bypassing, or there is a leak in the brake system. (mc, lines, prop valve, calipers, wheel cylinders, etc)

2. With the brake pedal pressed, start the engine. If the pedal sinks slightly, the vacuum booster is okay. However, if the brake pedal height does not vary, the check valve or booster is faulty.

3. With the engine running, lightly press the brake pedal. If the pedal sinks more than 3/8" (10mm) in three minutes, the master cylinder is faulty. (If the A/C is on, a slight change in the height of the brake pedal is normal.)





Leak Test


1. With the engine running, press-and-hold the brake pedal, then turn the engine off. If the pedal height does not vary while pressed for 30 seconds, the vacuum booster is okay. If the brake pedal rises, the booster is bad.

2. Turn the engine off and wait for about 30 seconds. Press the brake pedal several times using normal pressure. When the brake pedal is first pressed, it should be low, then gradually rise with each consecutive compression. If the position of the pedal does not vary, inspect the booster check valve.

3. Disconnect the vacuum hose (check valve built-in) at the brake booster.

4. Start the engine and let it idle. There should be vacuum available. If there is no vacuum, the check valve is not functioning properly. Replace the vacuum hose, and retest.

5. With the engine running, pinch the vacuum hose between the check valve and the booster.

6. Turn the engine off and wait for about 30 seconds. Press the brake pedal several times using normal pressure. Again, the brake pedal should be low when it's first pressed, gradually rising with each consecutive compression. If the pedal position does not vary, replace the booster. If the pedal position does vary, replace the vacuum hose / check valve assembly.

Last edited by It Wasn't Me; 01-24-2012 at 03:56 PM. Reason: typo
It Wasn't Me is offline   Reply With Quote
 
 
 
submit to reddit
Reply

Tags
bad, booster, brake, check, civic, faulty, height, honda, pedal, replace, tech, test, vacuum, valve, varies

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump



All times are GMT -8. The time now is 03:41 PM.



2008 Copyright, InternetBrands Inc.
Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.

Honda and the Honda marquee are registered trademarks of the American Honda Motor Company, Inc. Neither American Honda Motor Company nor its subsidiaries or affiliates shall bear any responsibility for Honda-Tech.com content, comments, or advertising. Honda-Tech.com is not affiliated with American Honda Motor Company in any way. American Honda Motor Company does not sponsor, support, or endorse Honda-Tech.com in any way. Copyright/trademark/sales mark infringements are not intended or implied.
Emails & Contact Details