Hi Skillie
Having a bad run !
The fuel pump for the TD5 is a high pressure unit and it is located in the fuel tank. With the Defender the tank has to be dropped to get at it , or a hole cut in the floor of the car...
There is no other fuel pump.
It could be the fuel pump - but not very likely - normally threy are noisy before giving up the ghost.
Does your car have an EGR - it was discontinued round about 2004. The EGR will cause hassles at some stage.
Try diconnecting the MAF plug (situated just after the air cleaner box) - the TD5 often does better without a MAF signal...
Where do live ? If anywhere near Tokai you can call and I will run a diagnostic check for you - can sometimes highlight the problem immediately.
Dave