Transmission Lag

Hey, my explorer will rev up between 1st and 2nd gears and not accelerate. After it revs up it will accelerate just fine. When I stop, something will unstick underneath the floorboard. I could really use help on this, this has been going on for months and I cannot find the issue. There are no codes at all. The transmission fluid is perfect. It will not lag all the time. It can drive for two to three days and not do it. It does like to do it more often with the AC running. Earlier I was terrified, because when taking off from a stoplight, it would not go(the whole suv shook while it wouldnt go.) And then all of a sudden it jumped. Im so glad a car was not in front of me. Any ideas? I was told I could have a bad MAF but how can it be a sensor if my check engine light is off?

Thanks!