Kris Hansen

Ever since I picked up my B7, I've noticed that the serp belt tensioner vibrates like mad when the engine was running.. I've never seen an engine do that, but in seeing lots of videos of other B7s, it seemed like they all did that.

Well I replaced mine recently, and the new one does not vibrate at all, and interestingly, the engine is a lot smoother at idle.

So, if your tensioner pulley is vibrating back and forth with the engine running, replace the tensioner. They're not expensive, and they are easy to swap out.