Hey!
It is my first BMW and first non diesel car and I don't really know these engine well only that n55 is more reliable than n54, but not as reliable as b58.
I've changed belt, pulley and tensioner 4 months ago. Car is running smooth I love it.
However, as soon as cold weather hit 90% of my cold starts are with squeel from the front of the engine. I noticed quite wobble from harmonic balancer, but some say slight wobble is alright from harmonic balancer, but I have no idea what is a slight wobble and a wobble wobble.
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