ok some more info for you all to ponder over.
On the way home last night the temp didn't go above 68.
When I got home I had a play with the sensor that Gambit had told me about.
Cleaned the connection up a bit, checked that with it unplugged I was getting no reading on the mfa.
It didn't make any difference, HOWEVER after about 10minutes of messing about when I gave up the mfa was still reading 68. I'm pretty sure the oil temp on the mfa would drop by a few degrees after 10 minutes of switching the engine off???
It really feels like the sensor has gone dodgy and the resistance doesn't change above 70ish degrees. The reading stops at this point and will read this constantly until the temp drops back below this point.
Does this sound valid???
Oh and where the hell is the thermostat on a valver???