Bootlooping LG Volt will not connect w/ ADB
I solved this by booting into Download Mode (with the phone off, hold Vol+ while plugging in USB to computer).

There were some files that needed to be downloaded, including the LG Flash Tool, which was used to flash the stock ROM to the phone.

After flashing, the phone was in its original pre-activated state but at least it functioned!


Unbrick method for LG Volt (Boost/Virgin)  
GSM-Forum: LG Flash Tool  
Android Forums: Fix Factory Reset Status 2 errors - for an after-flash fix to boot