New Pads N Rotors, Now Pedal pumps up n down while braking

[UNFNick2k]

So I just replaced all the rotors and pads on my car because I had some warped rotors. Now when I'm braking the brake pedal pumps up and down while i'm applying a constant pressure with my foot. The pedal acually moves my foot up and down while braking. Called around and Brake Depot said they think it might be a bad rotor. I already topped off the brake fluid. Any ideas on what this might be? Thanks in advance

[hockeyman]

What do you mean by "moving your foot up-n-down"?
If it's pulsating quickly, then it sounds like a warped or bad rotor. If it's moving your foot slowly up-n-down, it may be your antilock system or master cylinder.

Try bleeding the brakes first. It may not be your answer, but it'll save you time and money if it is.

[UNFNick2k]

Turns out it was warped rotors right out of the box. Sucks that new rotors can be warped. Anyways got it fixed, thanks for the help.

[chas]

be sure to use a torque wrench when installing your lugnuts and install the lugnuts in a star pattern. its very easy to warp the rotors with improper tightening.

[93camaro_zzz]

Originally posted by chas:
be sure to use a torque wrench when installing your lugnuts and install the lugnuts in a star pattern. its very easy to warp the rotors with improper tightening.

This is true. And very often do you get a warped rotor new from a parts supplier.

[99W68Firebird]

mine has done that the past 2 brake jobs that my mechanic (works for Bendix brake company) has put on, so i dont know it cant be anytyhing defective because he woulda caught it.