When at a stop light, sitting, brake pedal slowly goes to floor. this only happens when its hot.
This has gone on in two other of my hondas. I replaced the power booster and it went away for a short while.

BACK AGAIN. PHUKK!!!!

Anyone know what this is?

no fluid loss.
no leaks.
no burned fluid.
everything in good shape to the eye.
everything so clean you could eat out of my engine bay off of any part.

HELP ME PLEASE.

 

just a shot in the dark, but maybe the brake booster check valve?? maybe? just a cheap fix if thats it...

Most likely tho, you have a leak in your master cylinder...not an external leak, but its probably leaking around the internal seal on the piston

 

Like he said, check the check valve. Also check the vacuum hose or wrap it in something, you might have a slow air leak.

Scroll down to the notes section on this page:
http://www.4gcivic.net/wp/reardiscswap.html

Hope that helps.

 

cool. thanx guys.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIred91 &raquo;</TD></TR><TR><TD CLASS="quote">When at a stop light, sitting, brake pedal slowly goes to floor. this only happens when its hot.</TD></TR></TABLE>

what the hell, this is clearly a master cylinder issue.

whats with the booster and check valve suggestions? that only affects vacuum pressure.

replace the master cylinder.

 

Yep it's a internal leak in the master cylinder. So replace the mc and your fixed.

 

I agree with ED7, its your master cylinder.

same thing happened to me a couple of years ago. Drove about 50 miles using my parking brake just to get back home.

remember to use OEM parts.

 

i had the same prob bought a new mc and i haven't had a prob since. next is to replace the e-brake cable it's strech to the limit.

 

Didn't you post a little while ago and everyone said its the MC?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by andrey320 &raquo;</TD></TR><TR><TD CLASS="quote">Didn't you post a little while ago and everyone said its the MC?</TD></TR></TABLE>I did a couple weeks ago I think
edit: still haven't replaced mine

 

I concur with the master cylinder, if it were your brake booster, usually the sympton is a very hard brake pedal, basically it won't even move. slack in the pedal means leaks, or air bubbles, you tried bleedin gyour brakes i assume? do so after you replace the MC too.

 

The pedal does not move fast at all, very very slowly, but enough that if you are on an incline and keep the pedalin the same spot, it will lose pressure and teh car will move, or it will start sinking slowly.

this is only on hot days, after driving a while in city traffic.

When my prelude did it, the only thing not new in the brake system was the power booster. And then after a while, the pedal pressure went waaaayyyy hard, but still sinks to the floor when its hot out and im in city traffic.

 

there is absolutely no question. replace your mc.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tyson &raquo;</TD></TR><TR><TD CLASS="quote">there is absolutely no question. replace your mc.</TD></TR></TABLE>

 

cool. I will try this and report.

thank you.