Purchased new cam shaft position sensor from Ford at a cost of just over £12 + VAT. It took no longer than 5 minutes to replace and the car has been fine ever since. Thanks for all who mentioned this.

I have a Mondeo 03 TDci 2.0 Ghia X 130 bhp and about a month ago started to experience similar problems to those already mentioned in this thread. At first, I didn't notice the glowplug light flashing, but the last three times, it has started flashing before the engine cuts out. I have had the RAC, a local garage and Ford diagnose the fault and nothing has registered on the computer. I have also had the fuel filter replaced, but this has not sorted out the problem. The local Ford garage said that they noticed a significant drop in revs when the air-con was on and suggested it needed a new compressor. I drove it for over a week without the air-con and it still cut out. I only usually experience this problem when the car is doing 40 mph or less, but the car is very difficult to maneouvre when power steering is lost.