Engine ONLY starts when ignition key is released

As per the title. My engine won't start ..until I release the ignition key.

Can anyone explain this symptom to me?

There's a video here [nomedia="http://www.youtube.com/watch?v=SIew2zyWPxk"]VID 00000-20110815-1748.3GP - YouTube[/nomedia] which shows it.

P.S. Forget me revving the engine, that's to do with another post/problem which is here: http://www.landyzone.co.uk/lz/f6/loss-engine-revs-power-poppy-running-160633.html#post1587427)

voltage drop to coil when turning engine over or faulty switch check coil +voltage when starting if it drops alot check supply feed and check to ssee you have 12v feed from back of ignition switch when cranking

Sounds like a faulty switch. Time to get your test meter out.

are they Ballasted coils on some ? or is it just the V8s ? . defo voltage drop to the coil tho .

I seem to have fixed this problem by changing the wiring on the ignition switch. Through trial and error I got the following configuration for my Series 3, 2.25 Petrol to work properly: