Need Help.....

My car seems to have a rough idle when the engine gets up to operating temprature. She started doing this before I changed the fuel filter and put Brand new AC Delco Platinum Plugs gaped at .060 and New Bosch premium wires in. Also tried the Sea Foam stuff. And it's still doing the same thing.
Just went yesterday to have the computer read to see if there are any codes coming up. Nothing showed up. Does anyone have any ideas what else might be wrong. Or which way I should go from here.

Thanks