Casio CZ/ VZ/ FZ - Pro Series

>   So the problem is now it only powers up for a few seconds before
>it crashes which makes it imposible to play.
>
>   What the heck should I do?

It's really pretty simple, use something better than aluminum foil.  Clean 
the corrosion (or whatever it is, probably corrosion) from the contacts with 
something abrasive.  And it wouldn't be hard at all to resolder or replace 
the power jack.