High rpm level occurred upon warm engine shut off and quick restart.

One of our '99's suddenly jumped up to 2500 rpm idle upon being restated after being shut off after a 150 mile run. I had to run it for a while before the rpms would drop back down to 750 rpm idle. It was virtually uncontollably running very high up. The problem has since subsided but it was kinda freaky at the time and sounded really stupid shifting into Drive at 2500 rpm with my foot on the brake (I was dropping my wife athe airport and had to open the cargo door with the ignition key, you know no door popper and then restart to pull away from the terminal.) Any thoughts? Thx

Did it maintain idle at 2500 or did it jump to that and then slowly come back down within a min. after starting? Mine will usually do this in the AM on cold starts not warm. I find that warm starts right after it's been shut down will actually bog the RPM's down a bit rather than spike them.

Thanks for the reply. It did not go down even when I put it into gear. It wanted to lunge forward. I had to hold it with the brake. It did this once before under similar circumstances, as well. It only went down after I drove it a bit. I think the engine was quite hot and when you take away the fan it gets even hotter and upon restart wants to compensate by jacking up the fan rpm or something? Any thoughts?