Thanks for your input:-
FYI the engine is the 4G63 (16v single camshaft)
I took off the upper timing belt cover. The belt looked very clean with no signs of cracking. I then turned the engine over in short burst and kept re examining the belt looking for weakness or missing teeth it all looks very sound and 100% OK. I note there is a second smaller timing belt 'B' which I can't see. This is described as silent shaft which I believe just reduces vibration so would not cause any starting issues.
Compression on all cylinders was very very close all at 200 psi
Just to clarify the engine up to now has never failed and the ECM has never been touched. The car was backed into its current position a couple of weeks ago with everything working perfectly! After a couple of days idle it has not been possible to re-start it. I know this all may mean nothing but it is all very peculiar! Looking at your list realistically which of the items do you think could cause the problem just in those few seconds when trying to get it to fire i.e. where should I focus for the next step?
Idle speed control = Not sure it would kick in so quick
Cam and cranksensor = You said I would not see the spark/injector spray sequence if this was wrong, but is there anyway it could be working but the timing has become wrong?
Air flow sensor = I tried starting with the air filter assy disconnected and also with a squirt of easy start no joy not even a single fire/misfire. I put my hand momentarily over the inlett (just before throttle butter fly) whilst someone turned the engine. I felt a slight vacuum. Is there anyway under these conditions I would not have got air as well as fuel (knowing the spray pattern looks good)?
Coolant temp sensor = Incorrect sensing either hot or cold seems impossible to stop me getting even a single spark.
ECM ground = Grounds can cause odd an odd sympton. Where should I check and or clean?
Fuel pressure = Spray pattern looked very good (nice fine mist)
Vacuum Hose = Not sure about this one.
Bad malfunctioning ECM/ECU = Always a possibility if it is possible for it to sequence correctly but somehow time the spark so it occurs say just before the valves close thus pushing unburnt fuel straight out, crazier thing have happened but I would have though I would at least occasionally get a misfire. One thing I also did (probably not recommended) to further disprove contamination and that the spark was good was to Tape each of the removed spark plugs over the top of there normal entry point then turn over the engine. I was able to get a small flash and small explosion as each of the cylinders fired as the vapours were expelled.
I look forward to your comments but at the moment it points to firing at the wrong time but would I never get a fire/misfire?
If we were to conclude that it is say the EMC what else could I do to disprove anything else before possibly sourcing/changing this item?