ROUGH IDLE!!!!! FIERO!!!!! PLEASE HELP?

i have an 84 fiero and i have an idleing problem when i start the car it idles fines it runs great for 10 to 15 minutes and then starts to idle low around 500 to 600 rpms in drive and 600 to 700 rpms in park and kinda goes up and down and also when it warms up i can here it cutting out a little but only when it warms up things i have replaced: spark plugs,ignition coil,ignition module tested ,tps, temp sensor, these things only happen when the car is warmed up any ideas? thanks for the help