Okay so I've just began playing New Vegas on my PC for essentially the first time, and I have quite a few mods installed. I'll be playing new vegas and about every 10 seconds SOME npcs will begin to barf and just stay in a continuous cycle of barfing. This glitch has occurred with the ghouls in space suits, and the electrocity engineers added by a mod. All of the mods I have installed I found through a series of videos that go by the titles of Fallout New Vegas Mod Clinic, and Fallout New Vegas Mods Ultimate Wasteland Edition.

Mods I have installed:
A Familiar Friend- The Pip-Boy 2500 Pipboy
DUINVv04
EVE- Essential Visual Enhancements- EVE v1point14
Fallout New Vegas Redesigned
Flashlight NVSE - FlashlightNVSE112
Nevada Skies- Weather Effects BETA and URWLified - Nskies 0-6 Data
Nevada Skies Weather Effects BETA and URLified - NSkies 0-6-3 ESP
One HUD (oHUD)
POCO BUENO Texture Pack - Poco Bueno Hi Res GS Watertank
POCO BUENO Texture pack- PocoBueno Skeleton Transparency Fix
POCO BUENO Texture Pack - PocoBuenoTexturePackV5
Project Nevada
Project Nevada - DLC Support
Project Nevada - EVE Support
Project Nevada - WMX support
Quick Trade - Quick Trade
The Mod Configuration Menu - The Mod Configuration Menu
Unified HUD Project - UHUD
Weapon Mods Expanded - WMX
Weapon Retexture Project

You have some mod troubleshooting to do. Start by unchecking ALL mods except FNV and the DLCs and see if the problem goes away.