i kinda have the same thing i changed the rear brakes but i think it might be cause i didnt push/turn the piston all the way in. if the car is cold they work fine but then when it gets hot the brake pedel is all the way to the floor and theres like bearly n e braking. i tried bleeding them just incase but nothing. could this be because the piston wasnt turnd all the way in??

 

i dont think thats it...my brakes do the same thing man. Its frustraing as hell but i think they are just shitty calipers. IM gonna try new calipers, rotors and lines. I think it could be hoses collapsing also.

 

well the thing is it never did this b4, the usto be perfict, then when i changed the brakes it started to do this

 

try adjusting your ebrake cable at the handle. the problem with 240 rears is that the ebrake cable is supposed to actually pull back the piston some. if the cables not tight enough, it;ll let it drag too much

 

its tight..