Non starting Mk3 gti 16v

[tallpaulr]

I was wondering if anyone could help me out because I've no idea where to start.
Over the weekend the old girl was running fine without a care in the world, Saturday night just as I was about to head off to work started up no problem, turned the eninge off for all of 15 seconds and now the damned thing won't start!!!
It's turns over fine, the fuel pump is priming, but there's no spark. I pulled a plug and turned it over and nothing happened.
I at first assumed it was to do with the alarm/immobiliser but I had the company that fitted it out yesterday and it's working fine, they said something about the factory immobiliser packing up and said that it could have been the transponder in the key. But I know it's not anything to with that (I've tried the spare to).
So now it's process of elimination time and was looking for some help, so any suggestions will be greatfully recieved as I'm stumped.

[DazVR6]

Sound like the coil, if theres no spark thats my bet, they tend to just pack up with no warning.

[tallpaulr]

It's just the fact that mere seconds before it was running and then absolutely nothing do they really go that fast?

[Len]

Yep they can! And as everything was hot at the time...........

[tallpaulr]

I'm a firm believer in the fact that you've got to work your ass off to fix a problem, if it comes easily it's good to be true, and it seems this is one of those uncomplicated quick as you like wam bam it's done jobs.
It's in situations like this where I lay a fiver down on the odds of it being something terminal.

[Pete Taylor]

If it's a factory immobiliser then the car wil start when you turn it over but then it'll die again after a second or so. If it's completely dead then it sounds like a dead coil or an ignition switch problem