Make sure the the glow plug relay is working, do this by turning the ignition on after about a 30 seconds you should hear a 'ping' from the r/h front (the blue box under the bonnet) If it does then try replacing the glow plugs, these are under the box that sits on top of the engine, If it is fuel starvation then it could be the little filter thats in the fuel tank on the end of the sender unit, you have to remove tank to do this. Its very easy to do.
clive hughes, January 2006