I have a 92 civici hatch with rear disk brakes. I recently changed the rotors, pads, and the lines to stainless steel brake lines. But the problem I'm having now is that when i hit the brakes the pedal will stop but slowly start going down until it hits the floor. I have bleed the brakes more than once and I can't figure out whats going on. Has anyone ever had a problem like this, perhaps could it be the brake booster? Does anyone know? oh yeah if your wondering there are no leaks at the piston, brake lines, or the connections. thanks for the help.

 

have someone step on the brakes and look at each wheel from underside with a flashlight, then check booster. you are definitely losing vacuum.

 

Same thing just happened on my wife's '93 Accord, it turned out to be a bad master cylinder.

 

I recommend bleeding the brakes again.

This happened to me before after I've changed my brakes to Integra ones. Many people in this web site said it was the booster, but when I bled the brakes several times more, the problem went away.

Make sure you bleed the brakes all 4 coners until there is absoulutley no air coming out. It should be one continuous stream of brake fluid.

 

Did your brake system have these symptoms prior from changing to disc brakes? If not, its not your MC. Its a coincidence if it is. Read this, a friend of mine and myself had a similiar issue:

 

Air in the brake system just makes it feel spongy. You have a bad master cylinder...

 

When I converted to 5lug, I had to swap the entire rear trailing arms out, needless to say, it left a huge puddle of brake fluid on the ground. I have speed bleeders and I swear I was bleeding them a whole 10 minutes.

The pedal just kept on falling to the ground. I later fixed it by doing a pressurized brake flush/bleed

Note:

1) Its VERY common for air to accumulate in the MC after swapping out the trailing arms because normally alot of fluid drips out.
2) Not in ALL cases does "spongy" feeling brakes result to a bad MC
3) $5 paypal bet that its not his MC

 

I have the same problem. I have a 96 ex and swapped to Si rear suspension....Mine is so spongy. Ive heard a few things, a couple have told me it might have to do with the proportioning valve, bleeding the brakes...i dont know. Im switching the valve tomorrow, and gonna rebleed and see what happens!

 

I have a similar problem...I hope you're right.

 

Make sure you always bleed the furthest caliper from MC, and work your way in..which would be..1-passenger rear, 2- driver rear, 3- passenger front, 4- driver front. Otherwise, you're keeping air in the system. If you can't figure it out, take it to a good brake shop and have them flush the fluid, can;'t hurt to have new fluid in, and they'll get your brakes as tight as factory!!