weird ilding problem

[240ShaneX]

Hey guys, this seems strange and I thought I'd check to see if anyone has seen this or might now what it causing it. I have a KADE, and tonight it has been doing this weird idle when I put it in neutral/clutch in. When the engine is warm, when I clutch in/neutral to stop, say from about 2500rpm or so, the engine will continue to rev at about 1800 rpm for 10 seconds or so before dropping to normal idle (no my foot is not still on the gas! lol). This is one of the first cooler nights weve had here in FL (about 55 deg), and I think I remember it taking a little longer than normal for the revs to drop last year when it was cool out, but not near this long. Any ideas what might cause this??