brakes on 2004 Acura RSX

so i just changed my rotors on my car. now when i am driving there is a scraping sound with a pulse. its not constant but its like there is a bump on my rotor. i did not change the pads because they where not bad. i have no iidea why it is doing it.

Asked by for the 2004 Acura RSX
Sounds like you may have bumped a backing plate when you replaced your rotors, so now there is rubbing sound, because the sheet metal backing plate is rubbing the wheel. It is easy to do and not hard to fix, just find the wheel and pull the metal plate away from the wheel.