I install my new Stoptech slotted rotors and Hawk HPS pads on my 03 sedan yesterday. The installation was easy. Today when I drove my car I notice that when I stop I feel like a pulse in my brake pedal, is that because the rotors are slotted or is it because the rotors/pads are bad?

 

If there's no vibration in the pedal, steering wheel shake or pulling under braking, then yes, it's likely just because of the slots. I have heard of this happening from slotted rotors.

 

I have stop techs, and do not have anything like that..
Braking is smooth.