running bad

i have a 1991 chevy 1500 350 engine 189,000 miles it had a miss to it when the motor warms up and when you come to a stop it runs real rough.somtimes it runs great all day then sometimes it's real bad i changed the coil,plugs,cap,button.wires.did not help at all it has hardley no power and now its starting to smell like raw fuel.i done a compression test i had 5,at 180,2,at,155,and 1,at,135 i can not figure it out because of the run good somtimes run bad other times so please help.....thank you in advance for your time