Hi,

I have a 2007 A4 1.8T manual. On the way home yesterday I had a sudden drop in power. The engine started sputtering and I could hear an engine knocking sound. Pulling over I could see the tensioner in sync with the knocking sound which was from the opposite side (back) of the engine. The sound seems to be near the top of the engine. Idling seems to be fine when in neutral with a slight vibration which worsens dramatically when driving. The stuttering is worst when accelerating, then smooths a bit at the top of gear, then worsens again after gear change when the revs drop.

Any help on this is fully appreciated.

Grant

 

I don't know about the 1.8T engine, but on the 2.0T, the top-rear of the engine is where the cam chain lives. These engines sometimes have the chain tensioners fail which loosens the cam chain. I think you're going to have to disassemble some stuff back there, pull the cam chain cover, and look at the chain/tensioners. That sounds like what's going on to me.