I am currently having an issue with my Mini's brakes. They are spongy and the pedal is nearly to the floor before I get any braking power. When I do get braking power it is minimal. I have bled the brakes twice and it seems to fix the problem for a short period of time but in short time the issue is back.
I understand that I likely have a leak in my system somewhere which is allowing air to enter. Since I do not have a leak on any of the calipers or drums I presume it is an issue in either the brake master cylinder and/or the brake servo. Have any of you had success just changing the master cylinder on a servo setup and had any luck... or should I change the entire servo/master cylinder setup?