96' Voyager running problem.

Im hoping someone can give me some insite here because Im a bit lost right now. I just finished putting head gaskets on a 96 Voyager with the 3.3 engine. I also replaced all other related gaskets, intake, exhaust, injector o-rings etc. I got everything back together and got it started. It starts just fine, but has a poor idle quality. I checked, and double checked for vacume leaks. I made sure all my plug wire were in the right order. I even checked for any bent prongs on the connectors. So far I found nothing that would cause this condition. I hooked up my scanner, and reset all adaptives after cleaning the throttle body.(What the trouble shooter in my scanner told me to do). There were also no codes present. I started it back up, and the problem still exists. It doesn't smoke, or make any noise it just won't idle correctly. If you rev it up, it starts to smooth out once it gets upstairs. I took it for a test drive, and it acted fine once it was at road speed. Ive pretty much run out of ideas. If anyone out there might have some advice, it would be greatly appreciated. Thanks.