ABS issue

[98tahoedude]

I have a 98 tahoe 4dr 4x4 and I started having a problem with the brakes. They will make a wierd noise like the ABS is kicking in (even when Im not pushing the brake) and when I do push the brake the pedal is really stiff like there is no power brakes. Then they will go back to working like normal but the ABS light is on. Whats wierd is when they do this the ABS light goes off for a little bit then comes back on. I cant find anything mechanically wrong with the brakes. I put new rotors and pads on the front a few months ago and they are still in good shape, fluid is normal, no signs of leaks. I am guessing its some kind of module or sensor for the ABS but without taking it to the dealer and having them hook it up the computer I have no idea where to start. Has anyone had any similar experience or have any idea what it might be? Thanks!

 

[1999HOE]

i just replaced my wheel speed sensor it was going off at speeds between 5-12 mile per hour and also whether it was brakeing or not at you will need to go to a dealer tho i tried to go to a local shop they wanted me to replace the entire abs system plus the dealer will have to recalibrate the sensors...