I am having a very frustrating problem with my car. When I crank the car cold it starts and idles perfectly. It does have some minor hesitation but other than that it runs fine however when starting the car warm it's a whole different story. When I start the car after it has been warmed up it initially starts fine but then as the idle is coming down to normal it just tries to stall out. I can give it a little throttle and keep it from going dead but it will not idle consistantly for around 30 seconds to a minute. While it's doing this if I rev the car hard or pull out and hit the throttle it hesitates and sometimes backfires I've also noticed smoke coming from the tailpipes. I can't tell what color the smoke is because I'm sitting in the car trying to keep it running. I have noticed this problem before but it seems to happen more often during warm weather so obviously it's been much worse lately. I iced the intake at the dragstrip this past weekend and let the car sit for about thirty minutes and when I cranked the car it idled perfectly with no hesitation and made better power than normal but that's why I iced the intake in the first place but it seemed to help more than it should have. I only made one pass so I'm not sure if it did or not. I have pulled the codes and the only codes I get are EGR and smog but I have eliminated both these systems so that's normal. I also get a system rich code from both banks. I replaced the O2's a few weeks ago and I'm still getting those codes. Sorry for the long post but I'm trying to give as much information as possible. Any help is greatly appreciated