Does it feel like its taking off in 2nd ? If it does then check for a blown fuse, or damaged wiring going down to the transmission. Make sure the mlps (glorified neutral safety switch) on the drivers side is plugged in good.
Did you not get any transmission codes from the pcm ?
Code reader doesn't communicate so that's another issue.
Taking off? It feels better in 2nd but still not good, shifting to D then light throttle it "feels" like it wants to shift again. Really odd, it makes a sound I could best describe as a wooshing noise and RPM's drop.
Check your fuses, the fuse for the data link connector should be fuse #16 in the inside fuse panel, it should be a 15amp fuse. If its blown you can't communicate with the pcm, check for other blown fuses while you're there