Yeah,try some fresh fuel,I always find it helps but it certainly sounds fuel/airleak related as if it were ignition I'd say it wouldn't even fire.
Sorry I can't be of much more help but it sounds like your on the right path.
Conversely,have you checked that the fuel cut off switch hasn't been inadvertently activated?
It's on the passenger kick plate from memory.
I'm sure you can test for fuel pressure on the injector line via the little tyre style valve,be aware it may squirt out under a fair bit of pressure so take care with your eyes.