Where did you purchase your camshaft sensor? I'm going through the same problem as well right now. Got my first one from advanced auto parts, brand was BWD. Installed it, light went off, then light when back on, read the same thing. Aftermarket/non-OEM camshaft sensors have been known not to read properly apparently, so you should go with OEM. Autozone actually carries them. It says Duralast but its actually original BMW equipment. Just got one today, been running smooth... will see what happens in the next couple days.