Ok after a bit of poking around on the stalling issue the IAC Valve seems like a good place to start. Everyone who's had it replaced has it throwing codes left and right though. My Focus hasn't thrown a single code... Well, now that i think of it, the car threw a code back in July for temperature sensor. I pulled it out and cleaned it and it hasn't thrown that code since. Otherwise, no codes.
I'm interested in the PCV Hose though. I had a tuned EG hatch for a while (don't judge me) so I'm familiar with the system in Hondas, but I'm completely new to Ford. Is there a PCV Valve on the Focus? Exactly how is the Crankcase ventilated?
By the way, when I took the car in previously (code for temp sensor) the tech who checked my car said my breather hose has a crack. I asked if that could cause stalling and he thought for a minute, said "I don't see how it could" and told me I'd be better off to go to the scrapyard and find a used one and put it in myself. Truth is, I don't know what a breather hose is, but I'm going to assume it has something to do with crankcase ventilation, right? Is it possibly another name for a PCV Hose? Thanks again.