I've got an iphone 2g 8GB at first it only power on when I plugged in the usb cable or wall charger.

Tt also stuck in emergency mode and when I power off it would not power off completely, it flashing the screen with apple logo back and forth.

It would not let me unclock or do anything and also it when I plugged in it would not show the battery charging indicator.

I bought a new battery from Ifixit.com and replace the new battery, now it power up without having to plugged in but other problems still exist like without power off completely and wouldn't be able to unlock....

I'd appreciate if any body know how to resolve this issue.