Not sure how to ask this, so here it goes. A couple days ago I noticed that when sitting at a stop light or stop sign with my foot on the brake, it sounds like I have some sort of air leak coming from under by the brake pedal. I had my wife play with the brake pedal while under the hood, and I can feel the brake booster kind of vibrate with my hand. The brakes all function fine, with no change since this issue. The vaccuum hose is attached, and it is not leaking from there. Only if you stick your head under by the brake pedal you can hear a sort of humming noise, as well as feel the brake booster kind of vibrate when the pedal is at a certain position. The sound only seems to happen when you are lightly holding the brakes down. Also, all fluids are at proper levals, and there are no leaks from the rack or anything else. Any suggestions? Thanks everyone.

 

IDK honestly, but if you find yourself in need of a boost LMK. Mine works find but I am about to take it off so i can replace it with a hydroboost for more power. I can sell you mine if you want.

 

I'm guessing that the diaphragm ( I killed the spelling) Is not behaving as it should. the diaphragm is located inside the can behind the master cylinder. it's not a at home fix it in my opinion, let the mechcanics deal with it.

 

Well, I haven't really had time to inspect it further, but I will keep you posted (WEED). Still has been acting the same with the noise/feeling, but no change in brake functions. Hopefully this week I will have more time to tinker with it.

 

i have this EXACT issue right now. please let me know the outcome. i have checked all vacuums and fluid levels....no issues. if u squeze the pedal right it makes a high pitch air noise and the pedal will goto the floor if you keep pressing harder. the brakes work fine and never been an issue. the noise just happened this week.

 

maybe check to see any bolts are loose?

 

Well, still no update on this issue. It has not gotten any worse, but has not resolved itself either. I have had zero time to mess with it with my work schedule. If anyone else can chime in, by all means please do so. If I happen to find the time, I will revive this post. Good luck.