My 1998 A4 2.8 Quattro has been displaying some unusual symptoms. The brake work fine a driving speeds, when the car goes below about 5 mph the pedal pulsates as if I am slipping. In addition, when I am accelerating and I hit 1500 rpm it applies the ABS, hampering my acceleration. I know the Bosch 5.3 is problematic, but the ABS light is not on. Would my problems be fixed if I just replaced the ABS control module? I would appreciate any advice or ideas.