S70 braking problem

[Einstein]

My '97 S70 has a braking problem. The power breaking doesn't always work when the car has just been started. The break does work, but it requires more force. After 100m of driving the problem goes away and the brakes operate as normal.

What is the most probable cause of this problem and is this something I should give immediate attention?

thanks.

 

[Roger Mills]

In an earlier contribution to this discussion, Einstein

My '97 S70 has a braking problem. The power breaking doesn't always work when the car has just been started. The break does work, but it requires more force. After 100m of driving the problem goes away and the brakes operate as normal.

What is the most probable cause of this problem and is this something I should give immediate attention?

thanks.

I'm not sure whether it works after 100 metres or 100 *miles*. Which is it?

If it's 100 metres, it sounds like you've got an air leak into the vacuum chamber of the brake servo - allowing the vacuum to dissipate when the car is parked, only to be re-charged when the engine has been running for a little while.

It's not too serious at present, but you should get it seen to in order to prevent it from getting worse.