Starting to get this a lot almost on a daily...I'll start up the car (04 GT) and about a minute or so later after idling at 600rpms, it'll start bouncing up and down between 600 and 1000rpms at 1 second intervals and it doesnt stop until I start moving the car. Once I start driving it the problem stops and doesn't come back if I stop again and am idle at a light. Could my MAF be dirty, have an intake vac leak, or something? I check my air intake and it appears to be good. I'm not sure what to do and the problem is annoying the hell out of me.