Hi. I have this very similar problem also. To cut a long story short, I had a free MOT with my car (included in the price from the garage that I bought it from), which was 200 miles away from my home. After driving my mk2 clio 2002 diesel from the garage i noticed a strange grinding noise. This was 2 months ago, and It has still not stopped. The garage says that they have put new front brakes and pads on, which I dont doubt as this problem is only occasional, I think the problem is electrical.
What happens is, when I first start the ignition and drive away, upon gently braking the car judders, and continues to do so untill the car has come to a stop, with limited breaking power. the strange thing is, if i put my foot down in second gear straight away to about 40mph, the juddering will stop when i brake and the cars full braking potential will be restored. At this point, the abs and service lights are on. I'm almost actually developing a technique to making it stopping do this. The strange thing is, if i just drive the car up to a steady speed of about 50mph, in 5th gear, the car will seem to 'sort its self out' and the abs light and service light will again come on. I know the car has had new brake discs and pads, and i am very cautious about putting it into a coventry garage in fear of being hit with huge garage bills. I cant keep on driving with it like this as if i did have to stop suddenly in "juddering mode" then there is a much greater risk of an accident.
Has anyone else had this same problem, in the irregularity of the breaking problem? Previous posts seem to suggest that people have had braking issues, but perhaps not irregular ones.
any feedback of what I could suggest a garage looks at would be fantastically appreciated.