Strange noise

My 2009 35i has started to make a low thrumming noise almost like morse code
It sounds like its coming from behind the rear bulk head.
Can't hear it when driving but when I moved the car into the garage today to vac it seemed quite loud.
Could this be the fuel pump ? as I've not noticed it this loud before.
 
Does this sound like it could be it http://www.z4-forum.com/forum/viewtopic.php?f=45&t=26857&p=379792
 
Back
Top Bottom