So yesterday was the first hot *** day here @ home. I drove my car all day, and notcied they were very spongy. By the end of the day my pedal was hitting the floor at lights... I knew it had to be my master cylinder...

So today I pick up a new one, a new caliper (because I've always had a little trouble with one) and new front pads, and some Dot 3...

I'm waiting for my buddy to get off so I can use his lift, so I decided to drive my car around the block.. I stopped on every steep *** hill, and no pedal change. My brakes feel completly fine now... and I never touched them... any ideas?

 

its still your master cylinder, or some other leak in the brake system. but if youre not losing fluid, then its your mc that has an internal leak that when it heats up, gets worse as metal expands.