Thanks for the advice folks. Have it booked into a Ford garage tomorrow morning.
Frightening how many Ford Diesels have this problem, there were literally hundreds of posts online about it.
So far the most likely suggestions from various forums seems to be:
Crankshaft/Camshaft sensor problem:
Failed injector or loosing it’s calibration and needs re-coded
Pressure sensor on fuel pump
Fuel filter and fuel gauge sender unit
EGR valve needs replacing
Fuel pump disintegrating or being blocked which in turn could be affecting the injectors
Fuel pipes being a bit knackered having holes in it and drew air into it
Other points raised in some posts were:
In 2003 Ford issued a service bulletin about TDCI mondeos cutting out due to failure of the block connector for the fuel pressure sensor. A kit containing the connector was made available. This seems more likely to me to be the cause so Im going to check that out when I get a chance.
The injector pump, injectors and all the pipe work etc might have to be replaced as it is a well known problem with the ford/jaguar pumps that due to the new non sulpher diesel not lubricating the pump as well as it should, the pump starts to break up and contaminate the hole system.
So the garage needs to do a pressure check, followed by an individual injector leak-off rate test. If the injectors are OK; they’ll need to think about air getting into the fuel line or a failing pump.
We have now had a turbo seal leak repaired and a new cam sensor fitted, will wait and see if it is fixed.
The ECU has picked up a fault on a sensor and will limit power if its going to cause harm to engine, so if ran in limp mode for to long it will shut car down.
I’m having the same problem and again I have spent over £300 on a fault that is still there. I have had the EGR valve changed, the fuel sender changed, the injectors re-coded twice and the problem is still there