Ford Mondeo '02 Tdci Glow Plug Light Flashing

[Barrex]

I have a 2002 Ford Mondeo 2.0L TDCi. While I was driving it yesterday, the glow plug light started flashing and the car was fairly down on power. Judging purely by the noise, it would seem that the turbo still works fine. I stopped the car and was able to restart several times without any problems, but the lack of power continued throughout the day.

When I went to start it this morning, the glow plug light was still flashing and the engine would not turn on. It was fairly cold outside (2°C), I understand that may be part of the problem. Tried again at lunchtime, 5°C, but still nothing. The car tries to start, but the revs don't go above around 500, whereas normally it would idle around 800rpm.

Any feedback as to what might be the problem and a general idea of how expensive it might be would be greatly appreciated.

[VHG]

Duplicate question, already asked below.

[Buenchico]

Some possibilities here:
http://forums.moneysavingexpert.com/showthread.php?t=4238471

[SpikeyBush]

when the glow plug light on my Vectra starts flashing it means the DPF needs a recharge by taking it for a spin up the motorway like my hair is on fire.