Well, after a right old battle with Fiat, I have got no further.
Fiat Technical won't allow me to demonstrate the fault.
Fiat Tech won't come out and test the car for the fault unless I can guarantee the fault will occur at 70mph (i can understand this one).
So, at the moment, as its a company car, its over to the boss who is speaking to Fiat Finance and quite possibly giving them the car back which is a shame really.
Today however, it seems the fault is a bit more continuous. I have noticed it on little short journeys from the start.
Something i missed out. The other day i had a very good run home, the car faulted worse than ever, there was a smell of burning oil (possibly not from my car tho) and the boot floor was raving hot!!!!