i have a 03 audi a4 2.4 v6 1 of the cam chain tentioners was bad so i went and brought 2 new chains 2 new tentioners and gaskets took it all down to the garage to have fitted they have fitted it BUT now it has a funny knocking sound WHAT COULD IT BE???? ive left it at the garage as even the machanic was confused and didnt know what it was being a audi fourm ime hoping for some helpful advice anyone had a problem like this bofore ??????????????