Bump n' Grind [not the good kind]

[A3_Rider]

When I am driving I hear a metallic scraping noise from the back of the car, at first it was as if a steel girder (!!) was under my car, I pull over and check and nothing is there and the exhaust is fine not loose.

Today I drive off and it happened again but I carried on, it got so loud I thought either the car would fall apart or the exhaust would drop off. Then I slow down, nothing, after going over a slight bump its back and went away after that.

There is no loss of power or drivability, braking, etc. I am assuming someone has threw a few stones in the exhaust and they are deep in, but the noise doesn't act continious.

My car has done this twice now over the last month and a half.

A3 V6 DSG

 

[Red-Eye]

I had a simular problem once before, it was a stone caught between the rear disc heat shield and the disc. Does it make the same noise in reverse? also going in reverse knocked the stone out ;-)
Give it a go, hope this helps.

 

[FranA3]

as said above if its not a stone then it could even be the heat shield its self could have bent a bit and is catching the disk that makes a nasty noise to fix that literly push the heat shield away a bit from the disk its easy you don't have to push it a lot just a little bit , you can even do that with the wheel still on if you have got big gaps in your wheels to get your hand in there saves taking it off lol

 

[Farhan]

Had this sound to dude! randomly my cars a 1.8tfsi was going into car park all of a sudden hear this terrible noise as though the exhaust has fallen off and its scraping the floor. Look around the car nothing drive off and it happens again...Go over a bump it stop i was like huh...Never happened again.

I to think it was maybe a stone or something caught in between brakes or a rotating part which caused it.

 

[zseano]

I had a simular problem once before, it was a stone caught between the rear disc heat shield and the disc. Does it make the same noise in reverse? also going in reverse knocked the stone out ;-)
Give it a go, hope this helps.

^^ This. I had the exact same problem.. I was driving and bam scraping noise so I pulled over and everything was fine. Drove a bit and still there.. got worse. Pulled out and took wheel off and found a big stone stuck in rear disc heat shield

 

[TM]

I've had the same thing previously also, like others have mentioned its most likely a stone stuck between the heat shield! Horrible sound!