E800 wont turn on!! Please help asap!!!

Hi,

I got a Samsung E800 which i flashed with the fast and furious mod. All was working fine untill this morning! I needed to change simcards for the day so i took the simcard out of my E800 and put it into another phone.

This evening i came home, put the sim back into the E800 and the phone wont turn on anymore! When connected to the charger it will turn on and then after clicking the menu button, it will just turn off! Also if the charger isnt in then it wont even turn on!

I doubt its the battery since the battery is brand new and only got it a few days ago. I'm wondering if its the mod i put on but how do i delete it and just have the normal samsung E800 firmware on there?

When connected to E800 downloader 1.3 it says

*****************************************
Downloading Terminated
*****************************************
StackPointer not received
Downloading Pre Loader. Done ( 3.4s)
Target Detected !!!
Turn On The Mobile!!



PLEASE HELP ME!!!