I will put it in drive and when I press the gas nothing will happen, the engine will just rev like if it was in neutral. Then after a little bit it will catch and start going. What's happening here?

Your fluid is probably low. Check it, and refill as nessesary

What if this happens and you arent low on fluid?

Vacuum Modulator Valve. It's a $20 at any parts house.

Exactly the same symptoms, plus 2 qts. trans. fliud 'disappearing" into the intake each week, slow acceleration, and pinging.

I replaced mine last night. Two hours. Included a half hour attempting working from underneath before giving up since I had no picture of what I was looking for, then a 1/2 hour removing the console and pass. seat, and folding the carpet back & removing the hump access panel. Another 1/2 hour tinsnipping more room on the access hole and removing the trans. heat shield nut. Finally, the modulator is only held by a small stud and a vacuum hose, which drained a 1/4 cup of fluid!

I had done a search on this forum prior and got some good hints on the replacement. Thanks.