I just replaced the pads and the rotors and I have the same problem. I think It might be electronic. I noticed a small steel sprocket on the inside outside of the front axle right below the shock strut. My friend said that is part of the ABS brake system. That small sprocket is broken, it has a small 1/4 inch gap in it. Could that be the cause of the brake pulsation. The problem only occurs when I depress the brakes hard now