Starts great but immediatly wants to die

[EMB2580]

Ok, like the title says, my car starts up great but within like 2 seconds the idle drops and the car starts sputtering, and makes a slight backfire sound, but not like a POW! more like a "thump" sound. If I rev it up for a few seconds the idle goes back to normal and it's fine. When it's warm and I start it, it's fine. I had a post awhile back about it not wanting to start when warm but started great when cold. seems like it's doing the oppisite now. Also, it doesn't seem to have a miss while driving, so I don't think fouled out plugs are the culprit, I'm still leaning to the IAC valve being dirty/worn out. What do you guys and gals think?

 

[CerberuS]

codes?