I have a 1996 Audi a4 b5 2.8 Quattro...I recently got a knocking noise to the car and I got the belt tensioner replaced. Now we took all the belts off and started the car. Once the car started the knocking noise started again...my mechanic said its my motor knocking...so I'm gonna get a second opinion from another mechanic and see if it's really the motor going on its way. The car drives fine and there isn't any roughness to the idling or even shifting gears and highway driving etc. I'll be really sad if I had to sell the Audi.

 

Can you post video or a sound clip of the noise?

 

ill post a video of my car in abit...my timing belt and all the pullys and other misc belts were all replaced. The knocking is coming from the engine i put some oil stablelizer but the knocking is still there...The knocking sound does not affect the cars performance at all...it comes in when the car is fully warmed up.