I have 3 disco's but my '98 with 90k miles now has a very occasional completely soft brake pedal. I suspect that the original fluid is still in the system and that there is an issue with the master cylinder. The other possibility is an intermittent loss of vacuum, but the pedal travels all the way to the floor, not firm with no stopping power.

Thoughts, and my thanks in advance
kevin

 

Start by checking for a vacuum leak, if there are non then you need a new master cylinder.

 

Spike, there is a M/C rebuild kit, wouldn't that be a more cost effective option? Or is it 6 of 1 1/2 dozen of the other?

 

Why not get back to the basics and flush your brake fluid before it becomes so acidic that it eats up every seal in your system.

 

thanks, guys, only have the car for several months, but it is an opportunity to do that now

 

I have no personal experience with the master cylinder repair kit but I have heard that it works half the time.
If it were me I would just buy a new master cylinder.