Sounds like my car....

my idle air control valve is bad...

its supposed to adjust your idle air to make up for the more drag from your Ac compressor...

i had to take it off and clean out all the carbon...

put it back on and i was ready to go again...

if thats not it it could be the valve under your throttle body... cant remember the name of it... i think cold start valve.... not to sure tho