I'd try bleeding them again, air can cause this.
But, this is almost always a sign of a master cylinder failing. I bet if you unbolt the master cylinder from the brake booster and slide it out a little to look at the booster, it's soaked with brake fluid inside. The engine is sucking up that fluid and burning it.
If this was a Manual (no booster) Brake car, your firewall and floor would have brake fluid from fluid leaking out of the master cylinder.
