Thanks twinreal, I have reconnected it for now and will see if I can find a better earthing point, any suggestions on where is a good point? Although I guess the thread of the bolt goes all the way through to the engine?
Thanks all, I am hoping to give the engine bay a good tidy up over winter so I will look at doing that then! I see on some cars that they don't seem to have any of the lambda cabling there, can it all be moved to a more discreet location does anyone know?