Having hiccups not a backfire more like misfire after a bumpy road
 

So im pretty new to thia whole jeep thing 3 weeks ago I aquired my first one! And boy am I excited to get into this! Long sotey short I have an 1989 sport with the inline 6 and a auto transmission im running 33's and there is plenty of work to be done until I would be satisfied, well **** who am I kidding ill never be satisfied and always want more haha. Anyways I ran into my first issue which stumps my limited automotive experience. After driving a bumpy gravel road the other night as im pulling off onto hard pavement and excelerate I began to feel what I would call a misfire not loud enough for a backfire almost like a pfsss sound coming from under the hood and only under acceleration. The problem contuniued yet wore off as a drive back home begging with was wgat seemed to be maybe as many as 10 occurances and two stop lights later turned into one or two. I then checked pluggs spark plugs intake system which i had to tighten the air filter (aftermarket) and drove again with only one pop under accelerationandtoday absoluetly nothing given I have not stepped on it hard yet did the same things which would have caused it yesterday curious to see what may be the issue and any advice. Thank you in advance I really appriciate and im sure so many more questions will arise and maybe one day be the one to give advice.