1999 JGC loud air pressure coming from brake pedal! Please Help!

Reply

  #1  
Old 04-14-18, 01:49 PM
Member
Thread Starter
Join Date: Apr 2018
Location: United States
Posts: 2
1999 JGC loud air pressure coming from brake pedal! Please Help!

My 99 JGC is once again giving me hell! The brake pedal now continuously hisses air out pretty loudly. It use to just be when I'd let up off the pedal, but now it does it the whole time the Jeep is running. The brake pedal itself looks and compresses normally, It isn't hard or doesn't go to the floor. When I'm driving and push the brake to slow down the pedal itself feels like it nudges back against my foot..... Im stumped and I need to figure out whats going on its the family vehicle there for my babies ride in that car and i got to have it safe.

Any ideas and or opinions are VERY welcome!
Thanks in advance
 
Sponsored Links
  #2  
Old 04-14-18, 02:08 PM
Member
Join Date: Jan 2013
Location: U.S.A.
Posts: 1,508
Unless you have done a major rework, rest easily because it doesn't have air brakes, so my first though is that what you are hearing is a vacuum leak rather than a pressure leak. The door controls on your heating and cooling ducts are probably vacuum operated, so I would search around that area for a line or fitting that is loose or broken.
 
  #3  
Old 04-14-18, 02:50 PM
Member
Thread Starter
Join Date: Apr 2018
Location: United States
Posts: 2
aka pedro,
I will definitely look into that, thank you! I was also thinking there could be a leak brake power booster or possibly damaged diaphram in the booster?
 
  #4  
Old 04-14-18, 05:07 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 46,255
Welcome to the forums.

Has the brake fluid level gone down ?
The hissing in the booster could signify a leaking master cylinder.
 
  #5  
Old 04-15-18, 12:20 AM
Marq1's Avatar
Member
Join Date: Sep 2016
Location: USA MI
Posts: 2,832
Sounds more like a leaking brake booster not a master cylinder!
 
  #6  
Old 04-16-18, 06:08 PM
ukrbyk's Avatar
Member
Join Date: Mar 2010
Location: USA/ Pacific NW
Posts: 3,316
Leaking brake booster resulting in stiff brake pedal.

When I'm driving and push the brake to slow down the pedal itself feels like it nudges back against my foot.

Booster diaphragm likely ripped.
 
  #7  
Old 04-16-18, 07:10 PM
Gunguy45's Avatar
Super Moderator
Join Date: Dec 2007
Location: USA
Posts: 21,023
The brake pedal itself looks and compresses normally, It isn't hard or doesn't go to the floor.
Doesn't sound like bad booster to me. Disconnect the vac line, plug it, and see if you still hear it.
 
  #8  
Old 04-17-18, 07:44 AM
Member
Join Date: Nov 2007
Location: MI
Posts: 2,576
Check online or at your dealer to see if there's a recall for the brake booster. Covered models get a rubber boot over the booster to keep rain & snowmelt that runs down the hood gap from entering the booster below. The water causes the booster can to rust and can also freeze--ripping the diaphragm. Frozen water in the booster can limit pedal travel, causing a crash.

Of course the booster should be tested, whether there's a recall or not.
 
Reply

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes