Car wont idle (wont stay on)

[Kevin]

So basically after my hg.. my car will start and run.. but wont stay on (wont idle).. it just dies. when i start it up.. it just hits 1000rpm and then slowly dies. i thought it was the iacv.. so i changed it... and nothing was different. the car will stay on if i hold on the gas.. or if i really adjust the idle screw on the throttle body but i was told that that shouldnt be adjust and that the idling is controlled my the iacv. when i do ajdust the crew though the car starts loping idle.. which is understandable. so basically i'm stumped. i'm open for suggestions. btw when i hold the rpms at around 700-1000 .. the car is really rough and above 2000 rpm it is smooth but there seems to be the occasional misfire/backfire sound. i changed the plugs and wires already.