It should say Brakes go soft in the title, but i am tired and messed up. So this has happend to me twice while driving. The first time i was going over a RR track and when i pressed on the brakes the pedal sank to the floor and it felt like all i had was the master cyl kicking in. The second time happened today, i was coming over an overpass and i had to stop for traffic. The pedal sank to the floor so i had to downshift to slow me down. Once i let off the pedal and press it again it has pressure like normal (both times). Any other time the brakes work normally. What is going on here? Is my brake booster failing? The rest of the way home i babied it and kept a clear distance to reduce the chance of getting in an accident. The first time it happened was 3 days ago, and the second time was today. One was at night time one was in the middle of the day.... Any ideas?
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
Brakes Go soft
- Thread starter JERM
- Start date
Something like that happened to me about 2 years ago. My pedal went to the floor one time, I pumped it up, and have had normal brake operation ever since. The fluid level was fine, the condition of the fluid was fine. I don't know why this happened, but has never happened since.
When my first gen started doing that.. it was intermittant at first and easiley "shrugged off"...
After while it became "all the time".
It turned out to be the brake booster.
when the pedal "fades" if you pick your foot up and repress the pedal it would work fine.
I also has a "hissing" sound.. from the floor board when the pedal would fade.
After while it became "all the time".
It turned out to be the brake booster.
when the pedal "fades" if you pick your foot up and repress the pedal it would work fine.
I also has a "hissing" sound.. from the floor board when the pedal would fade.
No, the brake light does not come on when it happens. The pedal sinks to the floor then it feels like i only have manual brakes because the car is trying to stop. I noticed today that if i pump the brakes while the car is idling, the engine begins to run rough. Also leads me to believe the brake booster is losing vacuum. Any thoughts on that?
The Anti Lock brake came on tonight after i started my car. I shut it off, started it again and it was on again. I tested the brakes until i felt confortable with its stopping ability. I drove about 4 miles down the freeway and then parked the car. The anti lock light has not come on since then and i have drove it a couple more times.
A failing booster will make the pedal HARD not soft.
If you go press the pedal softly, does it go to the floor? But when you push it fast/hard, it holds pressure?
Sounds to me like your seals in the master are failing allowing fluid to pass by causing the pedal to go to the floor.
If you go press the pedal softly, does it go to the floor? But when you push it fast/hard, it holds pressure?
Sounds to me like your seals in the master are failing allowing fluid to pass by causing the pedal to go to the floor.
Its a new master cyl from NAPA.... it could be just a bad one though. If i push on the brakes hard or soft they dont sink to the floor. The only time it sank to the floor was after hard acceleration (not WOT but she was pulling good) then i had to let off the gas quickly and hit the brakes like when you are accelerating onto the freeway and someone cuts you off and you have to hit the brakes. The brakes feel fine and work normally around town if i drive like a grandpa. Again, if the car is idling and i pump the brakes the engine starts to miss and shake like it has a vacuume leak, but i dont see or hear one.
Oh....ok, now that you explain it again, it definitally sounds like a booster. Crawl under the dash and hit the brakes when the engine is running, do you hear a "hisss" when you hit them? When my Stang's booster when out, it would hiss BAD when I applied the brakes, but you could only hear it if you got your head down there.