Hi everyone, For a little while now our semiauto / funshift A160 has been making a little whirring sound. Sort of like a very slow helicopter, but the sound speeds up with the revs. It happens when in neutral or in gear. It is a whirring sound that is steady at idle and increases with acceleration, even when not in gear / stationary. Here's a video What's that engine noise? Mercedes W168 A160 Whirring Engine Sound - YouTube We just spent $1600 having the drive belt tensioner and belt changed because they thought that was causing the noise, then eventually power steering pump replaced (because the steering stopped working, not because of the noise). But the noise is still there. Help! THey said they'd have to dismantle the engine just to diagnose it, which is hugely expensive. I'm worried it's the timing chain and it's going to just snap one day and leave me with a worthless car. Any ideas of things I can do to just test it out / isolate the possible cause would be really great.