The whisteling noise is the vacuum inside your engine is too high, and air is entering either your rear of front cranckshaft seal. Most of the time your seals are good, but the problem is your PCV valve. To test your PCV bring a cigarrete lighter (or other source of flame) close to the PCV , if the flame is sucked by the little hole in your PCV that means it is not good and need replacement. The bad news is: to replace your PCV you need to replace your Valve Cover. Also, after you remove your coils and before you remove your spark plugs, you can spray with compressed air to clean it.
Welcome back! I missed watching your content on your E84 as it's a very niche car. Seeing that you removed the plastic cowl and some of the intake, you could of done a BMS Cowl Delete and BMS intake 🙈
Great videos pana’, Tengo la misma X1, y now I'm have a F”$! problem with the headlights, they stop working & I don't find anyone who can repair them, and a replacement is around $1300, any ideas....ufff,
