[mbrault]

Ive been trying to figure out what this problem is but i cant seem to figure it out or find it on any other forums , i have a 2011 bmw 328xi with the N51 motor basically around 2k rpms i get a slight rubbing /grinding noise that increases in sound as the rpms go up , no ac on and no air on , i do have a cat back exhaust but to me it sounds like maybe a pulley related issue. I was wondering if anyone had this problem. Also when im in a drive thru or pull up to a redlight the car will start surging , not hard where the cars going to shut off but it surges really fast until i hit the pedal slightly or roll forward a couple times until it wants to stop so im not sure if thats something related to the grinding/rubbing noise upon acceleration. Ive replaced coils/spark plugs , valve cover with integrated pcv done by bmw. Also i cleaned the MAF and changed the air filter , ive changed the ps rack and pump 5k miles ago with genuine bmw and the car has no codes and never wants to throw one to point me in a certain direction so im lost.

[mbrault]

https://youtube.com/shorts/dZt64lBLZ...WEfO2XGMfpao5l

You can hear it best between 10-12 seconds , its hard to hear over video because of my exhaust but worth a shot.