CV joint? Or maybe something else? Motor mounts?

[tripletdaddy]

The rpms jump up because you have disengaged a loaded engine that will then easily increase in rpm. The computer/electronics have nothing todo with this. Then the momentum of the transmission, ie. fluid, torques converter, shafts, etc. will continue to turn but will "drive" the engine so the engine rpm doesn't just instantly drop to idle. Usually you think of only a stick shift trans as being able to restart your engine if it stalls while rolling. Well, with this momentum of the auto trans and the "driving" of the engine by the trans, I've been able to restart the engine. I didn't think it could be done, but I proved myself it could.

[zorobabel]

Ok, here's a situation:
If I go downhill at about 60mph in overdrive, when I put it in neutral, the rpm jump up like I said. But, as I catch more speed (let's say 75), the rpm go higher, like adjusting to the speed of the vehicle. This is what's odd to me.
Now I've tried other cars in the same situation, and the rpm drop to idle. I guess it's just the way the AX4N works (or at least mine).