my 3.9 engine stalle when put in gear..HELP

hey guys. Your opinion here. I just put new engine in my 2000 dakota. 3.9 v6. Im worried i put Distributor in wrong. It will start and idle ok but as soon as you put it in gear it spits and shakes and stalls out imediately. I thaught that if i put dist in wrong that it wouldnt idle as smooth as it does but a friend told me that it still would crank and idle so i may have put it in wrong. I have changed tps sensor but the other sensors are stock. Could it be MAP or the crank sensor? trying to get this thing running today. help!! what yall think.

when you put dist in,did you just drop in and try to set timing or did you do it by factory service manual?procedure is more than just dropping in and go.see service manual for correct procedure.

Mine did that one time a couple months ago and has never done it before or since and the truck runs perfect, totally random on my truck I guess, it is also an automatic 2000 3.9 dakota.