When I first picked up my car in June, the guy hadn't driven it at all in 2 years and not much the 2-4 years before that. Driving it home I noticed a small miss. This went away after about 2 weeks of driving. Now I have my car put up for the winter and I go start it about once a week and the problem is coming back. However, this weekend I started it a few times and revved it up good and the problem is gone again. I'm planning on replacing the plugs/wires since they're 20 years old but is there anything else that would be causing this?

 

Start with the ignition system, but don't stop at just plugs and wires - check it all. The distributor cap, rotor, reluctor and pickup coil, ignition coil, coil insulator in the cap, everything. A lot of corrosion can develop in 20 years.