2000 ford focus no start?

i have a 2000 ford focus tddi i had a new fuel pump fitted june 2007 and then a new turbo 6months later after fitting the turbo the car ran fine (but i did not drive it because tax and insurance ran out) i started the engine and left it running for about 30minutes for 3 days and on the 3rd day i started the car and it was running for about 15minutes and the engine cut off and now it wont start i got a new battery and all the electrics seem to work and the car turns over but still wont start can any1 help me plz with this problem