F31 n57 slight noise at 1500rpm

[willmagrath]

Hi all,

I have a 330d that's just had a timing chain tensioner replaced. Before and after this, it's had a slight very light rattle at around 1500rpm. It doesn't make any other rattle noises on start up or idle. It's quiet enough that a camera probably wouldn't pick it up annoyingly. It hasn't got any worse either.

It goes away around 2500rpm.

Could it be some kind of auxiliary belt tensioner or something?

Thanks

[E-bmw]

First port-of-call for an engine-speed-relevant "light rattle" would be an exhaust heat-shield or similar.