Engine racing

Occasionally when I let off the accelerator pedal the
ICE will race. Has anyone experienced this racing condition.
It is not like the car revs up and stays there, it happens for about a count of two. and then it drops back down.

I have noticed this mostly when the engine has not been run
for a while. It seemed as if the "transmission" was slipping
in addition to the racing issue. any comments would be appreciated.
I just want to know if this is an anomoly with my particular car or if
others are experiencing the same phenomena

Matt