When mine had starting probs last week which sounds a lot like your it turned out to be a small hole in one of the rubber pipes in the fuel tank pick up pot under a a round metal plate with 4 srews under the mat in the boot. Only a 10 min job to check. with mine it was a very samll hole but was letting the pressure go back down and was like there was no fuel getting to the engine. Could also check fuel relay for the clik.
Hope the is of some help and you get it back on the round.
You were pretty close

After i checked all the fuses I read the ecu codes.....usual ones there plus 2 for the immobiliser.......so it looked like an immobiliser fault.......
Spoke to TB on the phone about it.......thanx for the time and texts TB

I checked immobiliser ecu wiring.....seemed ok.
Then garage boss decided to take a look.........
He checked the codes as well.......then decided to ignore them

And start with basics........is there a spark? yes ok next
Is there fuel.......off with a fuel line......no......so why not.....
Hes got a gizzmo....that can override relays........ie you can pull relays plug this in and it just basically shorts the wires when he presses a button......he explains to me....that if the ecu is stopping fuel.....then this is overriding it and so would expect fuel......so he tried it on the fuel pump relay........still no fuel.......
He then stuck a meter across the fuel pump......got 12v......but he couldnt hear the pump......so he took it out.....put 12v across it and it worked....so he put back in.....reconnected fuel line and gave it go.....my 2.2 started

But not for long, it cut out after about 30secs

He tried starting it again but it just cranked.......so he tried a very technical procedure

.......he told me to keep cranking it while he hit the top of the pump with a hammer......it worked

my 2.2 started again.
So thats the explanation......a tired fuel pump that needs replacing.
I guess the immobiliser codes where faults thrown up coz a dying/flat battery.
Total cost for today (altho not counting loss of earnings) was, for recovery to garage......and fault finding it.......£45..pretty good i thought........altho i now have a stick on holder mounted to my dash......full of his business cards
