Help--Brake Problem on 16v

[jasondew]

recently i installed some new drilled rotors, new pads, braided SS brake lines, and bled the whole system with high temp brake fluid. now i have a problem. after the break-in period i was testing the brakes and managed to lock up the passenger front wheel at high speed causing a flat spot on the tire. the "ANTILOCK" light came on which means that there was a fault in the ABS and the ABS shut off subsequently. also, at the end of a brake cycle (under 5mph) i feel the pedal pulsing like the ABS is activating, somewhat roughly. some times the "ANTILOCK" light comes on and sometimes it doesn't. i'm not going fast enough for the ABS to be necessary but it feels like it's coming on. also, after the light comes and and ABS has been shut off, the pulsing in the pedal goes away completely. what would cause these two problems? did i get my wheel speed sensors dirty during the brake job? do i need new wheel speed sensors? i took it to my mechanic who bled the brakes again for good measure and the problem persists. he said he can't find the diagnostics plug to test the ABS. is there a hookup for a diagnostics computer? any help would be appreciated.

thanks