Strange idle on mildly upgrade SR

[nismodk21]

ok i have a s13 with the red top sr..everythin is stock besides gt2871r,3inch exhaust,fmic..

i have a aem wide band not installed yet,apexi safc2 on its way,n a universal fpr i have no idea how to hook it to the fuel rail..

k the prob is it has a hard time cold starting..like its not gettin fuel but when it finally starts the temp raises pretty quik n when the cars warm it idles high n just sounds like s***..i have no idea what is wrong..plugs r black all of them..coils seem fine..im decently new so plz help n give detail plz...