Did you get the key out?
I have heard of failing ignition lock cylinders in the early 8's but not in the late models. It is a dealer only part BTW.
Just out of curiosity what is an 840 CSI? BMW did a Sport 840Ci in Europe with all of the CSI trim but not in the US. It still wasn't a CSI though--Need 4 more cylinders and about 90 more HP for that.