2001 Dodge Neon drivability

I have a 2001 dodge neon with 112,000 miles on it and all of a sudden one day it started chugging and lurching! It runs fine under wide open throttle. I have changed spark plugs, wires, coil pack, temp sensor, o2 sensor, map sensor, fuel pressure regulator. It has the right has the the right fuel pressure and and everything else checks out fine. The check engine light comes on and all it says is misfire cylinder 1 or cylinder 1 too rich. I am lost for words and don't know what else to do PLEASE HELP! Thank you.