wat is the iac valve and were is it at to check it

 

wat is the iac valve and were is it at to check it

 

i have slp long tube off road headers,y pipe, slp cats, dual dual loud mouth exhaust, i have the rears deleted in pcm but put them in to see if it would fix the problem, i have replaced o2's twice and have same problem again, i have idle problems and also runs rough sometimes until i get in second gear, not the transmission!