I just replaced my rotors and pads, didnt replace calipers but i lost all brake power (it goes to the floor) when the car is on. when its off it will pump up to a point and stay hard. wtf?

is this a brake booster issue, what am i missing here?

 

With the engine off pump up the pedal till its firm and then hold pressure on it while you start the engine. The pedal should drop. If it does then your power assist/booster is working fine. If not there could be a booster problem or vacuum supply to the booster has a problem. Did you open any brake lines?

 

Not to be a smartass, but like stated above, check your brake fluid level, just to be sure you have fluid to begin with. Also, if there is fluid, try bleeding them, and see what comes out. Maybe you just got air in your brake line somehow. and are you leaking brake fluid?

I just chaged brakes all around mine. Drums and guts, rotars and calipers and everything, and if you disconnect the caliper, there is a copper washer that creates the seal so you don't leak at the caliper.

Check everything and let us know. These are simple ideas, but ruling them out help us look deeper into it.