Oh great and wise HDI Gurus...

[Niall]

Starter motors don't really get lazy, if it's slow to crank your battery could be a bit weak and that can stop it from starting - the ecu won't fire the injectors unless it sees adequate voltage.

I can't speak for all ECUs but most have a working voltage of 8-18v so the first thing to give up working with a flat battery will be the starter won't crank or won't crank fast enough. Most ECUs will not inject though until they see a certain RPM from the engine, in the case of most I've come across this is about 400rpm. Once it sees that, it will switch over to its idle running.
HDi ecu may be completely different but thats my experience of all the ecus I've dealt with in the past.

Ahhh so maybe it could be the battery.... will swap it out see if that makes a difference..

So just been to fetch my new Crank pulley from my local parts place (they love me down there now lol) and just to add to the mix of potential cures.... they did say as my crank pulley is so fubared it maybe this that is causing the start up issue as it will be making the crank sensor move.... will see what its like in an hour or two when i have swapped it out!

Utter bollocks mate. Crank sensor is on top of the gearbox and picks up its signal from the flywheel so having a wrecked crank pulley won't make any difference at all in that respect.