jeep acts like it want to die when im at a light?

[John]

got a 93 grand cherokee 5.2L changed the plugs wires dist.cap which was a blast by the way an rotor an the coil run great even with 230k miles on it but after i drive it for awhile and i stop at a light it starts to idle really low an acts like it wants to die i can put in park an it idles back to normal but acts fine when im driving down the road well it had a miss fire only twice while driving dose any anybody have any suggestions im just afraid it will only get worse