My daughters S40 73,000 mi. is having a problem with the vacuum brake pump. I've read what I could about it and I'm just looking for others that have had and corrected the problem. When you first start the car you can hear the vacuum pump run and if you step on the pedal you hear it run. Pedal travel is normal but you have to use all your leg strenght to stop. At first I thought it was the semi-met pads weren't getting up to temp the way she drives(very easy). but she came home from college the other day and I had to move the car and realized its not pads. The pressure switch is working to turn the pump on and off so my question is, can the switch fail so its shuts off too soon when you first start the car? and give some, but not enough vacuum? Again the pedal travel is normal, not hard like if you had no vacuum to the booster. Thanks for any answers.