car randomly stalls while on freeway

Ok, so let me give a little history, this problem is very random and first began only after starting the car after I had driven it (like leaving a shopping center) it would start fine but I would put it in drive and press the gas and it would just bog down until it died. Starts right back up fine with no lights. I replaced both cam sensors and it occurred once more then has been fine for months until this week when I had been stopped on freeway while chp was clearing debris and accelerated fine to 70 then it was like I turned the key off and pushing accelerator just made it start shifting all crazy and I coasted off freeway where it died but once again started fine. Today I was driving at freeway speeds and same thing happens so I placed it in neutral let it die and restarted and all is good, still no lights. Any ideas? ive done just about all preventive maintenance on this car there is to do its an 2003 325ci with m56 engine and 78000 miles. any feedback will be apprieciated.