I do, it was the EGR valve. This is probably the one thing I hadn't even considered as like many people I thought only diesels had them! But no, the 2.0 petrol Duratec and I assume the 1.8 as well has one hidden away under a cluster of hoses and wiring loom To test it I simply unplugged it's electrical connector and went for a drive, no hesitation and no cutting out, drives flawlessly, it did however bring up an 'engine fault' warning light which I had anticipated. I have now cleaned the EGR valve out, reset ECU and fault light, EGR all connected up and no issues so far, I'm guessing it will only be a temporary solution and may happen again until I replace it.