Focus TDCI cuts out

[grpaway]

Can anyone help me with a problem I have with my Ford Focus TDCI 2002 115bhp car - I have had this problem for quite a few years now and no garage can find the fault.
The car cuts out when cold (say for the first minute or so of driving) when the revs become lower- like approaching a junction. This happens all the time in winter and in summer when there is an extra load on the engine - like AC going. If it was a car with a carburettor then one would think that the slow jet was blocked.
Ford have had it in several times and can find no fault/no code errors. My local garage (very good mechanics) can equally find no fault.
Any ideas
Thanks
GRPAWAY

[igiveup]

Have a look at this topic, could be of use??

http://www.pistonheads.com/GASSING/topic.asp?h=0&a...

[grpaway]

Have read the link - thanks.
I have no prob with the glow plug light and the crank sensor has been checked.
The engine will begin to cut out (during the first mile of driving or so) when the revs are above 700. It will still cut out even if they are about 1100.
The peculiar thing is that when the engine is warm and the revs are reduced - like approaching a junction - then there will be an automatic injection of fuel to stop the engine cutting out - but this does not happen when the engine is cold.
GRPAWAY