Will not boot form any drive

Just got this G3. I knew that it might have hard drive issues, so I plugged in my external firewire, and started holding down my option key. I selected the external drive, but when I clicked the arrow, the screen just blinked and nothing happened. The external drive boots other similar macs just fine, so I assume it is not the drive. Also tried several other install CDs, but again the machine will just not boot.

I connected to this mac in target mode from another mac and reformatted the HD and installed 10.3, but when I restarted, I just got a flashing question mark. I read somewhere that it could be corrupt firmware. I am not sure how to fix that. Any ideas would be appreciated.