96 grand Cherokee stalling when driving

I have 96 grand Cherokee and it starts sputtering
and stalling out after driving for a while it does it
faster when it's hot and doest do it at all when
idling when i give it more gas it just bogs down and
I have to turn it off and restart it then it usually runs
better for a minute only to start again so far in the
last month I have put in a new fuel pump and filter
ignition coil,ECM, spark plugs,cap and rotor, and
MAP sensor the upstream O2 sensor is probably 4-
5 months old none of it helped but it all needed
replaced anyway  I got it to throw a OBD2 code
once while it started doing it P0171 but no check
engine light nothing really seams to cause it
specifically it just happens puts no where I can be
on the freeway or taking off from a stop sign if I
put it in neutral it clear up but when back in gear
back to the same thing I don't know what else to
do