Brake Pedal Pressure Changing

[Birdster]

So parked the car up tonight. On the way home I noticed when braking that sometimes the pedal was normal with a bit of travel, progressive braking like you expect. Then, the next time it was quite firm.

So any ideas? Start with bleeding brakes/change brake fluid?

[clockworks]

Servo problem?

[Birdster]

I was wondering if it was servo/leak/pressure related.

[The Wookie]

If it was getting harder with use I'd agree and say something servo related, if softer then I'd say they need bleeding.

[phil633]

Had something like that on my a6 and brake pad lining had come away from backing due to corrosion.

[Fubar1977]

Is the fluid level where it should be or does it fall?
Is the Master cylinder leaking?