[bunnysloper]

UPDATE
SOLVED! I got the transmission fluid and the noise is completely gone.

My F10 with the N20 has developed a whining noise on acceleration around 1K-3K RPM and deceleration. The noise goes away at high speed above 60 MPH.

The car is at 126K miles and the timing chain and oil pump was replaced ~30K miles ago, with the updated kit.

Initially, I did think it was the timing chain. However, after closer inspection under the hood. The noise is coming the lower back of the engine bay. Most prevalent at the transmission. It’s clearly NOT at the bottom front of the engine, where the oil pump and timing components are at.

The noise remain on even with AC completely turned off. The alternator sits at the top of the engine so it’s probably not that.

I’m thinking that it’s from the transmission. The fluid has never been replaced and I do have the kit from FCPEuro ready for install. I just want to see if anyone had/has the same issue. I just want see if anyone experienced the same issues and if they were able to pin point what it is.

The car drives fine besides the annoying noise that is almost like an alternator electric wave noise.

Thanks in advance for your thoughts.

[Matgsand]

Pcv system not blocked causing chaos with main seals making whinning noises? Easy way to test pull off the oil cap with engine running and see if there is excessive vacuum in the engine