1998 BMW 328 White smoke

Ok I was not sure. Im a lexus tech and on toyota trans they have vacuum modulators that can go bad to allow atf to enter engine and burn. In this case I was thinking that because I am loosing my trans fluid somewhere and its not leaking out. I understand white usually means coolant but in my case it is not. The coolant level is not the slightest bit low, the car is not over heating and the white smoke DOES NOT smell anything like burning antifreeze (i have seen, smelled, and fixed many toyota head gaskets). Also found no water in oil or oil in coolant. I can do a compression test if you know off the top of your head what the pressure readingings should be, how ever I know compression is fine because engine runs smooth and does not miss. So what else can cause white smoke? I do know it had bad gas, car sat for a 8 monthes to a year. When I drained old gas it was very brownish. When new gas was put in the car ran much much better, still smoking. Any ideas other than head gasket? Think outside the box.