Hiya Mate,
thanks for a quick reply and the pic.
YES! I have now found it thanks to you.

The part of the loom is not clear in the pic, if you follow up from the temp sender you can just about see another loom dissapearing behind the head. (hence why I couldn't find it).
This goes to the Knock sensor, it was a bit of a tight job to click to two plugs together, infact I removed the fuel rail to gain enough access.

Having said all this, without you pic I would of still been scratching my head!!!

Thanks again mate