[lior]

Hello All.
Firstly i would like to explain that there is no bmw center where i live so i would like if anyone can help me diagnose some issues.

I just recently bought an M6 GC 2013 with 55k KM [ about 32-4k miles], it idles\cold start\warm start very unstable [100-200] rpm difference mainly and it can sometimes surprise with a jump of 500 rpm.

when accelerating hard i am pretty sure that the power delivery is not smooth, at the beginning i thought it may be just bad tires or traction control kicking in to stop the acceleration from happening now that i am a little bit more used to the car driving i notice that and it worries me.

Recently [ few days ago ] i was revving the car in my underground parking just to have fun with it but i notice that there is a loud bang from the exhaust when you rev to about 3-4k rpm and put your foot of the pedal.

i would upload a sound video a little bit later.

the gearbox sometimes slams a gear on slow speeds [ usually gears 1-2-3 ] on traffic its not that harsh gearing but noticeable , i never drove a DCT before so im wondering if it is normal? and if not i know there is a sequence in bmw cars that i can do to change the gearbox driving and reset it to default [ the one with the gas pedal when car is off etc ] do you think it will help?

Thanks for all the help guys!

P.S i know there is a forum for M6 but it is kind of dead, would appreciate if the post will remain here since M5-M6 basically is the same car.