Car misfiring while idling

[SR71]

Okay, the trouble bug has been hitting the Trans AM over the last month or so. I have no idea what's going on. For some reason or another, when I'm driving my car and come to a red light, stop sign, or drive-thru, my car starts "putting". Sometimes it's subtle, like one "bumb" and then it will smooth out, while other times it will start "bumbing" and wont stop like it's being starved of fuel. But when I step on the gas all is well. Haven't seen any noticable loss in power -- it takes off and picks up speed fine. The way it's behaving doesn't seem like I have a burnt out plug because it's not consistent. It's weird, it started out slowly, doing it about once a week, and now it's becoming more frequent. Changed plugs, wires, and fuel filter about 4 months, or roughly 7k miles ago. Maybe a vacuum leak? I don't know, but any help with be greatly appreciated because it's running me crazy.

Thanks

98 T/A A4 lid, K&N, FRA, Flowmaster, Hotckis STB,SFC, Optima Red top

[SeVeReDiStOrTiOn]

Check for any unmetered air getting through......clean the IAC(carb cleaner) and the MAF filaments(electrical cleaner) also and see it that helps. Sometimes you can get some oil build up from that k&n on the MAF and it can run shitty.