The other day I noticed that the brake pedal seemed softer than usual. I checked the brake fluid and noticed it was about halfway between max and min, so I topped it up and thought nothing more of it. However, this morning on the way to work the pedal was extremely soft and I'm quite concerned that there is a more serious problem.

Is it common for brake lines to badly corrode on a 10 year old Punto? I'm guessing yes, as I can't see what else would cause this problem. I changed the brake pedals and discs last summer and they've been fine ever since. I can't see how else air could suddenly have got into the system.

The other thing is that I already know that the caliper bleed screws are completely rusted and rounded off, so I don't think I'll be able to loosen them. If this is the case, I guess I'll have to take it to a garage. Any idea what I should expect to pay for new brake lines and the bleed screws sorting out?

Thanks for any advice - I'm not looking forward to driving home tonight :-(

I arent sure how much you can expect to pay but I imagine it will be down to exactly what is leaking, it could be a faulty slave cylinder or corroded pipes. If possible I would take it to a garage and ask them to have a look at it for you rather than turning up and saying 'fix this' to see what they think the cause is

If it was me, i would remove the back wheels and drums and have a quick look.

Could be a seal on one of the pistons leaking.