Another car wont start thread.

[Apnea]

If you remember back ages ago I posted pictures of my backbox missing, well the pipe that leads from the cat to the backbox gave up the ghost earlier this week and I was driving around with a pipe dragging on the ground.. anyway long story short... i pulled it out from under the car and I moved my car back to its place on the drive. I go out to the car just now and it wont start? Sounds like an immobliser thing? the engines turns over fine, and I can smell fuel but it just wont stay running, when I first started the car it started, then died straight away. I've checked that secret fuel cut off switch and its fine, the car usually runs fine, is there anything that could of just suddenly triggered the car not to start?

 

 

Urgent help needed please I've got work tomorrow at 10 and no way to get there otherwise eeek