I noticed that the drive belt tensioner on our 1.8T A4 has quite a bit of movement on it when idling. It seems to shake back and for pretty good, a lot more than my Silverado does (it doesn't move at all). Audi supposedly replaced it when they performed the 75K maintenance. Is it normal for the tensioner to have this much wobble?

What are the usual symptoms for a belt tensioner failure?

Is this normal? The car has a vibration when idling or at a stop and I'm thinking this might be one reason. Just enough that you can feel it in the seat, but doesn't shake the car or anything.

 

Does anybody know if the tensioner is supposed to move at all when idling, or is it supposed to not move?

 

It moves but not that much. The tensioner starts to fail when you hear a chirping noise coming from the belt. Keep an eye on it, if it was replaced then is probably alright.

 

Any solution to the vibration rattle from tensioner?

 

I just replaced my serpentine belt tensioner on my A4 B5 year 2000 today. It is tight in there but just three bolts hold it to the motor. I suspect your B6 is similar. Make sure those three are tight. If so, I would change it out, only about $30 part and your labor, which is kind of time consuming since it is so tight in there and I could only use a wrench, no ratchet.