EML light on, lose power, engine in safe mode
 

I have an '06 Cooper S and love it, although lately I have been experiencing a problem with the EML coming on, also the check engine light. The engine goes into safe mode with a loss of power. If I shut it off and wait a couple minutes I can get back home where I check the codes and have a P1688 code. (Mass Air Flow Sensor) which I find the '06 doesn't have. Instead I find it has a MAP (2) sensor. I have checked both and have found the one on the front of the engine has a small amount of oil on it. The other one on the drivers side of the engine looks fine. After cleaning the sensor and reinstalling it and clearing the code everything is back to normal for a while. Has anyone had similar problems and know where the oil is coming from.