Wierd noise on A4 Quattro....ABS?

[brushhead]

Hi,
I have a strange problem with a '99T A4 2.8 Quattro. When I come to a standstill, the ABS seems to be cutting in. I have replaced the front sensors, and installed a new Pump/ECU but neither of these have made a difference. I am about to replace the rear sensors.

Has anyone had this 'feature' before?

Thanks,

Rob.

[zollaf]

check the toothed ring that the sensor points at, give it a good clean and examine it for any damage. do this to all 4 wheels.

[clairebear1990]

Wierd, I had a similar problem. Here is the thread I wrote on it.

Hi Guys,

I have had my 07 Polo for 5 months now. Its ex-demo and has low mileage so is pretty new. But something went wrong with it last night, I have solved it but I am curious if this has happened to anyone else with a VW, not just a Polo.

As I was leaving work, and a couple of times on the way home I could hear a rattling sort of sound coming from the car. Although I was concerned I figured I'd have a look for anything when I got home.

However I was almost home when my car suddenly started making the wierdest screaching/scraping sound - it was just like someone scraping their nails down a blackboard! The sound was coming from the wheels. I stopped and had a look, couldnt see anything obvious so drove the rest of the way home.

When I got back I had a play about on the drive with it. The noise only happened in a forwards direction, when reversing it was silent. I figured that I would have to take it back to my dealer to get it fixed but was miffed.

So on a mission this morning I jacked each side up individually and took both my front wheels off to have a look. Their was nothing obvious bar some scratches in the brake dust on the inside of one of the alloys, of which there were none on the other side.

But after putting the wheels back on the car it was back to normal to drive - no noise.

Has anyone ever experienced getting a stone or something that would make the same noise stuck in their brake-pads?????????????????????? Theirs no way it could have been the rear wheels because there is drum brakes on the rear. It is mysterious and I'm concerned their could be something more wrong with it?????????????????????????????????????

I SHOULD ALSO ADD THAT THE BRAKE DISCS ARE NOT WORN - THEY STILL HAVE PLENTY OF CARBON COMPOSITE LEFT!

[B8 TDI]

Stones do sometimes get stuck inside the wheel or between the brake disk and the pad, this could very likely explain the screaching sound, reversing probably dislodged it thus no sound when you did. however, brushheads issue sounds more related to dirty or failed ABS sensors.