I have a 2013 Coupe s (n18) manual and I recently started having this issue. The performance of the car hasn't changed at least not noticably, and no codes or idle issues but I've noticed a few interesting things that I can't pinpoint the issue of.

​​​​​​First, while driving if I put it into neutral and its above around 2500 rpms, the rpms will stay at whatever it was left at and not drop at all for a while. It can stay like this for many seconds and I have to start to engage a gear for it to drop again.

Second if I am stationary and try to rev it, the rpms once again drop very slowly, and It seems to be most noticable around 2500 rpms and up.

The last thing I've noticed is once in sport mode, where the exaust would normally do the pops and crackling, it no longer does due to the issues above.

Anyone have any ideas?

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