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So here's my sad story. A couple of weeks ago my brake pedal was soft to return. Eventually I had to use my toe to lift it back up to normal position. I noticed this when coasting to a stop, after applying slight brake, the car just did not 'free wheel' but rather felt like a piston had locked up. A short while later while going up a hill I began to loose power.... At least that's what I thought at first. So more gas, downshift, and still slowing down. 10 seconds later cars in the middle of the road frozen- all pads fully engaged.

Managed to creep off the road open hood and pull off vacuum line from brake booster - after release of pressure then able to creep down the road to my local garage. Figured we should change master cylinder. Stealetship wanted $1100. I bought an OEM part from our host for $99. My garage installed and test drove - everything seemed OK. On my trip home same problem. Again pulled vacuum hose off booster released pressure and crept back to local garage. This time I purchased a brake booster and vacuum line ( with check valve) again from our host and had them installed. That had to be it. On the ride home- same problem. Brakes locked up tight. Had the car towed to the stealer ship where it's been for over a week. They haven't figured it out yet. Any ideas?! Car is a 1999 996. Fresh fluid and new Pagid pads
several months ago. Wondering if maybe ABS thing has gone goofy??