Rep Power: 0

got an 05 EX with 54k, ABS equipped. Sometimes when I'm holding the brake at a red light, the pedal goes down a little more after a couple seconds from when I initially stopped. I remember my moms old Civic having this same issue, and come to find it was a booster problem. The pedal does not drop all the way to the floor. The car isn't losing brake fluid, so I don't think it's a leak. Suggestion? Thanks again guys!

 
Rep Power: 285

A soft, somewhat unresponsive brake pedal is a sign the brake booster is on it's way out. Replace it with an RSX-S brake booster and you'll have a firmer brake pedal and better stopping power.

 
Rep Power: 235

Really? I've always been told soft pedal=master cylinder and hard pedal=booster.

 
Rep Power: 200

Yes typically you are right Lazlong. The BRAKE Booster can fail either way though I guess. Not sure on that one. Usually they do have a hard pedal because the vacuum assist diapraghm doesn't work due to leaks in it. Effectively you loose "Power" and have manual brakes. A sinking or soft pedal is either due to leaks of brake fluid, or a master cylinder that is bypassing.
Just because you don't see it on the ground does not mean fluid isn't leaking either. Fill the master cylinder up and watch the level for a couple days. The fluid level should only drop a tad as the pads wear. If it drops alot you definately have a leak. Look inside the rear tires, maybe a wheel cylinder is leaking or something...

By the way, you break glass. Cars have BRAKES. Usually don't nitpick, common though....

 
Rep Power: 285

Actually, your right on this Lazlong.

I was thinking a bit in the back of my mind that I'm mixing up master cylinder and booster, but I didn't check and I should have. I'm glad you corrected me.

 
Rep Power: 812

check the brake booster hose (between IM and booster). its the only one in the bay that looks 10 yrs older than the rest. its on my list of things to replace.

 
Rep Power: 235

But a leaking master cylinder wouldn't cause an idle problem, would it? Reason I'm saying this is I'm having the same issues (idle fluctuation in N and semi soft brake pedal) and now I'm thinking I have a bad booster (booster vacuum hose w/valve is fine). At $200 for the Civic booster and $400 for RSX booster I guess I'm gonna have to live with it for now.

 
Rep Power: 0

Thanks guys. I'll monitor the fluid to see if it drops. So far, the level has been holding. Pads prob. need to be replaced fairly soon as well. Damn, I better get on this.

BTW: Sorry bout that! "Break" vs "Brake." Believe it or not, I'm a column writer for a paper where I live. I'm so used to using "break" in my writing that I never stopped to think about it. :-P