Rpm hangs out while decelerating

[Jeepking1995]

I have a 93 yj manual with a stroker, when I'm driving it's fine but when I shift to neutral to slow down the rpm will drop from 2000 to 1200 hangout for a second or two and then drop back down to 800 and idle fine, only does this while driving and putting it in neutral coming to a stop, if I rev in neutral and let off the gas it will drop back down to 800 just fine does t hang up