96 SOHC running rough?

I was driving home last night and the car ran fine, but when i pulled in the driveway it kinda chugged a little. I got out and listend to the exhaust and could tell it was missing. It has been raining here if that could have anything to do with it. I pulled the plug wires and it is firing. Let me know if anybodt has any ideas. Thanks

common probs would be o2 sensor, egr, purge solinoid, although when I swapped in a new SOHC on my 95 I had a similar prob that was very random and then just went away after about a month.