dodgy starting....

i have a land rover 90 wiv disco 200tdi in it no matter what the weather it turns over a tiny bit and it fires up with no problems just a little puff of black smoke, but i went to start it this morning and it turned over and over and just before i thaught the battery was about to die it fired up ( i did use the glow plugs too),
then when i was at work it did the same thing before i left to come home...
im stumpped
any ideas?? jake

Air leak in the sysyem alowing the fuel to run back to the tank perhaps !!

it got alot worse i was on my way to work and it was chucking out smoke, i limped down the motorway at 35mph, but change over the injectors today and it is sweet as a nut now