Please help don't wanna sell
 

I have 2001 custom lesabre that has had over $1200 spent on the brake system only for the brakes to go out completely now. Literally the pedal was on the floor and the car started to roll forward anyway. I've have brakes rotors brake lines and master cylinder replaced and still I cant stop. I was thinking it was the ABS control module but I can't figure out which to order based off of my RPO codes. Can anyone help? Could it be the brake booster? At one point I was able to pump the brakes to stop but now there is no response from the pedal its very loose goes completely to the floor and makes a weird groaning noise now. I don't know what to do but I really wanna keep her can anyone help?

You didn't mention what you have done so far so I will wing it. The booster will not cause your problem. If you bled them, did you use the proper scan tool w/ABS? I understand the proper scan tool must be used when bleeding or you have to take it somewhere for the procedure to be done.. Also, the master cylinder can have an issue. Hope this helps..Good luck.

Sounds as a mechanical trouble more than electronic control. Air in the lines will always eventually migrate to furthest rear caliper or drum eventually. Pedal to floor is a mechanical issue. The ABS merely controls any wheel(s) from slippage and going out of control. Unless things have all completely changed.