I have a 98 dodge dakota 3.9 v6 2wd what could be the cause of a rough idle or the engine to stall?

I've changed the catalatic converter and the o2 sensor because that was whatwas throwing the codes. Now there are no codes shown and I can't figure out if it is the iac, maf sensor, or tps if it has 1. It idles real low like 6 or 700 rpm even when u first start it on a cold start instead of idling high and gradually decreasing as it warms. Then once it is warmed up while driving u come to a stop and it slowly idles down until it stalls and its 5 spd not automatic. Thanx