Hello all I have a 97 a4 quattro 2.8 when I speed up I have a loud knock and pop combined wit a low whine but after I back off it will stop and as long as I maintain speed it rides fine until to get above 40 then I got a wobble in the front end I thin its a axle but I am not 100% any feed back is thanked this is my first Audi I'm not as familiar as other cars