Dont buy the cheap stuff from Amazon/ China
Hard drive cable - MacBook pro was running loops with bad contact to harddisk. I checked this by reinstalling Lion OS X externally on a hard drive. This worked so my assumption that the cable was faulty proved itself.
I tried a cheap cable from amazon but people i tell you what a waste of time and money. You can get the perfect product here with Ifixit and you don't have to mess around with it like in the youtube videos.
It was an easy fix with this product from fixit so spend your money and get it done in the first go.
Buy it here. Problems solved