I need car help please!!?

[B e c c a l i c i o u s]

i just brought a 2000 hyundai excel and i went to park it in my garage for about 3 days and the battery went completely flat like you couldn't even charge it. So i went a brought 130 dollar battery new from the shop and it runs for a bit but if i leave it for a day the battery goes completely dead. i have a immbolisers i dont know if that would drain it? but what else can be draining the battery?

 

[Ray]

if your hyundai didn't come with an immobilizer from the factory it may have been wired up incorrectly and drain your battery, other than that being the problem umm...are your lights on? lol