I had this problem on my w reg golf gt tdi! I change both cam and crankshaft sensors also the glow plugs and still it didnt start. I checked all the fuel pipes that came from the fuel filter and notice the pipes were cracked and worn, so i looked inside the top of the fuel filter and i couldnt see any diesel. So i thought the engine had slowley sucked in air through the cracked fuel pipes over a period of time. This had caused an airlock in the fuel pipes thus starving the engine of fuel causing it not to start.I then got some diesel and poured it into the fuel filter and turned the engine over ! still wouldnt start! so repeated the same actions 4 times then the engine started. After this i replaced all the fuel pipes and the cars been fine.
steve piper (New Milton)
October 2010