Fixed some wires, now my car keeps stopping

Hi!

Had some issues with my tail light. So i followed the green/gray wire from the headlight switch, to the fusebox. There it went into a blue connector and to a red connector, on the rear side of the fusebox.
So I changed the (very corroded) green/gray wire with a new one and cleaned the connector-pins.
Tail light is now working, but my car keeps stopping.

Starts as usuall, runs normal for a minute or so and then it stops. Starts easily again, but stops after 10 seconds. Then it wont start.
Wait for an hour or so, and the same thing happens again. Starts, dies, starts, dies, wont start.

Tried to bypass my fuelpump, and it runs, but the engine wont start.
When the car dies, its like someone turns of the engnition. No stalling, or anything. Just dies.

Maybe I did something wrong when I was messing with the fusebox, but Im not really sure where I should start looking.

So, please, anybody out there who has any advice?? 

Okay, just discovered that it is a electrical thing. When it wont start, it turns out that i have no spark.
Hmmm.

sounds like old alarm or immobiliser perhaps, or your ignition switch or wiring. do the dash warning lights come on when its plying up?