Thanks mate!
So the new mission was to rewire the Knock sensor as the plug was totally missing. - Check.
Tried to get the knock sensor off but it was seized and the hex part was spinning inside the housing.. after a few hours of swearing.. I admitted defeat and called a mobile mechanic to do it whist I was at work.
Supposedly heating, a cold chisel and vise grips were required.. Hate to pay someone but if it can save me hours of messing around and getting pissed off, I dont mind so much.
Now that mission is over- I have to save up for my rear swaybar and nolathane bushes.. Might be a skint Xmas...