99 2.0 Grinding noise on braking - richard99
I have recently started to get a grinding noise on gentle braking, which appears to come from the back of the car. I have checked all of the pads (front and back) and they have plenty of life left. There is no scoring on the discs. There is no play to speak of in the rear wheels, top-to-bottom or side-to-side. When I rotate the rear wheels (handbrake off, gear selector in neutral), they spin for about five or six revolutions before coming to a halt, but produce the grinding sound that I hear, although not as loud as when I'm braking. If I brake hard there is no noise and the brakes are effective.

Any ideas?
99 2.0 Grinding noise on braking - Altea Ego
stone trapped in the pad. or defective wheel bearing
99 2.0 Grinding noise on braking - StanTheMan78
Have you replaced them lately? If so, are they genune or imitation? How many miles have you been using them? Did you check the disc thickness? How long has this been going on? Do BOTH wheels do it? Check the calipers for any oil leaks and / or sticky piston movements.
99 2.0 Grinding noise on braking - ronsam

I had the same grinding noise coming from the front of the car on the drivers side, like you i checked the disc and the pads.

I took the car to my local mechanic, he could see nothing so he removed the wheel, the back of the disc was slightly scored and the pad was worn also the caliper pistons were sticking.

This could be happening to your brakes.