Help - Spilt Coolant / Now not starting Whizzing noise and cuts out !

Hi,

Have picked up my New 2001 Octy 1.9 TDI Estate today,

The coolant temp gauge was intermitant, so have changed it from the one in my old octy (also 2001)

A fair amount about a cup full came out whilst changing, and then I noticed the rubber stopper bung at the top of the bell housing was missing,

The car starts and loudly whizzes and then cuts out, I was worried collant got into the housing, but dont think, so - what could it be, worried ive buggererd my now motor.

Could it be the crankshaft sensor getting wet ? 

Any ideas or advice really welcome

Thanks