'97 Taurus GL won't go when in drive

I have a '97 Taurus GL with around 53,000 miles on it. Today, while I was out, I put it in R without any problem. Then, when I put it in D and my foot on the gas, it wouldn't go at all. It also wouldn't go in N, OD, or 1. Any suggestions? The tranmission fluid is fine.

There is a sensor on the tranny that could cause this but usually it gives you some warning.

What kind of warning?

This is the trouble I've had:

1. Check service engine light. I was told it needed a new torque converter. Replaced that. Didn't help. Next, reprogrammed. Didn't help. Next, did more thorough testing (why didn't they do that in the first place?). Replaced something. That solved it.

2. Skipping. Haven't solved that one yet.

3. Revs too fast. I know the idle speed something needs to be replaced.

4. Now, it won't go in D.

It usually starts to slip, but not fully as you're describing.

If it was a dealer that looked at it they should have picked up on it though.

I should've used slipping instead of skipping. On Monday, after I filled it up, it was really bad for a while. This was going under 45 mph.

All of the above was done at the dealer. I live in a small town and don't have a lot of choices on where I can get it fixed.