Well lifted the hood to check the oil, and have a quick look around to ensure all is ok, when i spotted a bit of loom had come adrift from the engine block, and had been happily rubbing against the drive belt, down to the copper. The gap between the fan cowl and the engine is so small i couldn't even see if the wires were worn to the point of failing.
I decided to remove the wire from what turned out to be the oil pressure sender (sorry should have said its a diesel), so i could inspect, and repair correctly, after 10 min of trying to get the plug to unlock and release i finally had it in my hand, along with half the pressure sender, which disconnected like a lizards tail, without much effort.
Apart from having to wait 3 days for a new sender, why has it got a printed circuit board, and a chip in it????
Funny thing is, with it disconnected, when you start the engine, the oil light goes out, and only comes on after about 10 seconds, bit strange as its not connected.
Ideas anyone???