Hi guys. Im having exactly the same problem with my brake pedal going down to the floor when the car is idle. Did you ever fix the problem? because my car ended up giong to Honda and they say that they didnt know what was wrong.

 

you tried bleeding the brakes?

 

how u kno u have air in ur lines:
when applying brakes while car is in motion, it will feel soft when brake pedal is depressed and when brake pedal is depressed more, it becomes stiff.

how u kno u have a bad brake master cylinder:
when applying brakes while car is in motion and/or still, the pedal will feel real soft and braking can become difficult, when depressed more, there will still be little to no pressure and pedal will slowlysink. if continually depressed(like at a stop light), the pedal will sink to the floor with very little pressure.

bleeding brake lines:
u need 2 ppl if u dont have access to a bleeder machine. 10mm box end wrench. brake fluid(i suggest Honda Genuine). jack/jack stands. towels.

-jack the rear of the car and place on stands and remove wheels.
-starting with the rear right(passenger side) drum, there will be a little rubber cap covering the bleeder valve, shouldnt be hard to spot. take that lil rubber cap off.
-cover all paint near the valve with towels, brake fluid destroys paint, and i mean it'll eat right thru it..
-take a 10mm box end wrench and slightly loosen the bleeder valve(just enough to break it loose)
-tell ur friend to pump the brake pedal about 3 times and after the 3rd time, hold the pedal firmly depressed.
-while the pedal is depressed, loosen the bleeder valve untill fluid and air bubbles come out. once u think all the air bubbles are out, tighten the bleeder valve and tell ur friend to let off the brake pedal.

repeat those steps untill all air is out of that rear right side. repeat those steps, doing the left rear side 2nd, the front right 3rd, and the front left last. i suggest doing this a couple times on each side to be sure the air is out. also, after bleeding each corner, make sure to fill the reservoir so it dosnt fall below the"min" line.

replacing brake master cylinder:
can easily be done by urself, tho, u'll need another person to help u bleed the brakes after replacing..

-leave car on level surface
-place towels under the brake master cylinder and also around the fender or any part of the body that has paint. again, brake fluid literally eats away at paint so be careful.
-syphon all brake fluid from reservoir
-remove reservoir
-take off the 2 brake lines with a 10(?)mm wrench
-take off the 2 12mm bolts that hole the brake master cylinder to the firewall
-remove brake master cylinder
-be sure to remove the little round gasket that sits in the brake booster
-place new gasket in brake booster
-put new brake master cylinder in
-bolt brake mastercylinder back on the firewall with the 12mm bolts
-connect and tighen the 2 brake lines back up
-replace and tighten the reservoir back up
-fill with brake fluid.
-bleed whatever air may be in the lines

i just did this a couple days ago. my brake master cylinder went bad so i replaced it and also bleed my lines. i still have some air in the lines so i need to bleed em again, when i do, ill be sure to take pictures to help u guys out more.

any questions feel free to ask away.

 

this really helped thank you

 

I'm having this problem too, only mine seems to be random as hell. My brakes will work fine and then one out of ten times when I go for the pedal it will go all the way to the floor, still engage, but all the way floored. Most of the time the brakes feel normal though... so is it just bubbles in my lines? Or would you think it's the master cylinder?