Got a 94 accord lx w/o abs and seem to have some braking problems. When im stopped at a red light for example my brake pedal goes down little by little until it hits the floor. I have checked all the fluid and its ok i have noticed that maybe every 2 to 3 weeks i have to put brake fluid in. Now all my lines seem to be ok. Ive been doing some research and some people say that it could be my brake master cylinder going bad. I also read that if it goes down little by little with time then that it could be leaking into the booster. So if anyone can let me know anything before I go buy a master cylinder please let me know. Thanx

 

a brake pedal that slowly sinks to the floor when pressed indicates a bad brake master cylinder. Double check all your lines for leaks. If you recently did any work that could have gotten air into the lines try bleeding the brakes and see if that helps. Otherwise I would say it's the brake master cylinder.

a HARD brake pedal indicates a bad brake booster.

With a bad brake master cylinder you may not notice a fluid leak, like you had mentioned it can leak back into the booster. When mine went on my Civic it went FAST, like within 3 miles. I had to down shift while pulling the ebrake and hitting the brakes to stop.

When replacing the MC, clamp it into a vice to bench bleed it. I ordered mine from Honda and it came with rubber plugs in the ports, I took those plugs and cut out the bottom, then used silicone to attach and seal some small clear hose to the plugs. After drying, I put the plugs back into the MC and then routed the clean hoses back into the reservoir. I filled the reservoir with brake fluid and began pushing the rod on the MC to push the fluid through the MC and work out all the bubbles. Be sure to keep the hoses submerged in the fluid otherwise it'll suck air back in. Do this until the fluid in the lines are free of bubbles, it won't take long. Then on the car use a old turkey baster and remove as much fluid from the reservoir. Using a flare nut wrench remove the lines at the MC. Unbolt the MC from the booster and remove it. Now take the new one with the clear hose still attached to the car, have a drip pan ready. As quickly as you can remove the plugs with the clear hose and install the MC and brake lines. The fluid will drain so get the brake lines attached quickly. Once everything is attached clean up the area and start bleeding the brakes. Make sure to not let the reservoir go empty while doing this.

 

Thanx I just got a master cylinder ill see if when i change if it helps.

 

Hey thanx for you help just replaced my master cylinder and it worked. Apparently this problem has been going on for a while. Bought the car las year in april and pedal always felt a bit low. Didnt pay any mind to it but i should have. Now my brakes are really good so im glad i changed it. But thanx for all the help.

 

I have a question too. what would happen if the check valve for the booster vacuum go bad? or maybe the brake fluid from the master cylinder leak into the booster? It hasnt happen to me but Im just curious if anyone experienced that.

 

glad you got it fixed and I could help