geo tracker power amps

my friend recently gave me a 1000 watt amp and we tried to hook it up to use in my tracker but it wouldnt power it. i even bought a cap. and that didnt help either. it would only power the amp for about 1 sec. does anybody have any ideas on how to get more power from the system, or what mods i would need to do. or a suitable amp for use in a stock system? any advice would be appreciated.

my friend recently gave me a 1000 watt amp and we tried to hook it up to use in my tracker but it wouldnt power it. i even bought a cap. and that didnt help either. it would only power the amp for about 1 sec. does anybody have any ideas on how to get more power from the system, or what mods i would need to do. or a suitable amp for use in a stock system? any advice would be appreciated.
Are you sure your ground is on good.?

yea ground is just fine. we also tested this amp on a 04 ford taurus and a 96 carolla. neither of which could power it. but the amp worked just fine when we used a 12 volt lead from a computer. ( my freind has a huge 1000W power supply on his computer) and it worked fine. so its just power issues. my friend got the amp from his uncle who was using it in a 74 dodge charger. do you have a system in your tracker?