car dies out, but restart ok

I have a 2007 bmw328i automatic. car dies out and restart ok, here are the codes, P0302(cyl#2 misfire), P1415(the manufacture spec definiton is not available), P0304(cyl#4 misfire), P0300(random misfire), P0171(system too lean bank'1'), p0174(system too lean 'bank 2'), and repeat p1415 again. I did change a brand new fuel pump(VDO), oem coil #2 and #4, and reset all the codes, drove about 75 miles, car dies out like before and cam sensor code show up, so i replaced both cam sensors brought from dealer, reset computer, drove about 50 miles, car dies out again but restart ok, but no codes this time. I remember whenever the car is about to die out, it has a whistling sound. could it possibly be a mass air flow sensor? BMW pros please help! thank you!