did the rear disc swap, put on a new mc and still spongy. i didnt bench bleed the mc, but i bled the snot out of the system, got huge amounts of air over and over but bled and bled. seemed to get all the air out but still super spongy and goes to the floor when I turn the car on.

so, mc is good, booster seems to be good b/c brakes spongy only when car is on (wouldnt change when car turns on if it's leaking, right?)...

i dont get it and i'm going crazy, there is no loss of fluid and i dont see any leaks whatsoever in the system. could a bad caliper seal cause this? should i pull the lines off of the master cylinder and bench bleed it, then sart over? im stumped. bled and bled the system over and over. mc is new... i've had the swap on the same car with the same master and no troubles. any info appreciated...

 

i never bench bled the mc when i swapped rear discs onto my crx dx and ended up with solid brakes. i just threw everything together and bled the entire system the 2 person style. never had any luck with the speed bleed garbage. what are you swapping the discs to? when i did mine, i had to use an integra mc and brake booster and proportioning valve for the swap to work correctly.

 

i had the same swap on my ef sedan and it worked with the stock mc great. spongy as can be this time, changed the mc to a brand new one and they are worse. air? maybe im not bleeding right?

 

have an eg sedan, used 95 integra rear disc