my first thought is that you have lost booster function. Does the engine run properly with your foot on the brake at idle?

The booster is vacuum powered and for it to not work the vacuum has to leak which should make it run bad, or it is somehow not applied internally. The problem could be an ABS problem though. It would be very unusual though.

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician