Rep Power: 0

My son has a 2000 civic. Complained that his brakes were "weird?" Drove the car, had the brake pedal go almost to the floor but car still stops, but not well. Checked brake resevior and it is empty. Refilled resevior 2 nights ago. There has been no fluid lost since them but the pedal has not had any change. Its still going almost to the floor. Brake Booster?? Not a clue, since the fluid is not leaking out anywhere. Thanks in advance

 
Rep Power: 518

If the reservoir was empty, then there is air in the system and it must be bled out.
The air causes the low pedal. (Assuming that's all that went wrong..)

Go find a bunch of gravel.
Skid the car to a stop in the gravel.
Get out and see which 2 wheels made skid marks.
Start bleeding the brakes on the 2 wheels that did NOT skid.

You have to figure out where the fluid went, too. It didn't just evaporate into thin air.

Look all around under the car for evidence of fluid loss.
If you don't find anything, then unbolt the master cylinder from the brake booster and pull it out, see if the fluid has been leaking around the rear seal of the master, into the booster.


HTH

 
Rep Power: 0

Chances are the pads are worn down (and in need of replacement), when this happens, the piston in the caliper extends due to the lack of brake pad material, this extended piston uses more brake fluid and can cause the resivor to run low. Chances are he has air in the system, and all the lines should be bled (make sure you keep the resivor filled).

 
Rep Power: 0

i have the same problem for my 92 civic dx sedan I lost all of my breaks. I found out that my drivers side rear tire wheel cylinder went bad. I've changed it and my master cylinder as well but now I have no break pedal at all. any advice in what could cause this problem?

 
Rep Power: 0

Bleed all the lines

 
Rep Power: 0

I've done blead all the lines and still no break pedal whatso ever.

 
Rep Power: 156

since the master went dry, you need to bench bleed it again, once you have done that, re-bleed all the lines a **** ton of times in this order

Right Rear
Left Front
Left Rear
Right Front

the best way I found to do this is by using a 20oz bottle, fill it up 1/4 - 1/2 with new Brake fluid, fit a hose that fits tightly around the brake bleeder. Put the hose in the bottle and make sure it stays in the fluid and crack the line.

As you push the brakes, the air and fluid in the lines will exit the hose and when you pull the pedal back up, it will suck up Fluid instead of air.

Do this multiple times to make sure all the air is out and take it for a test drive.