[V8] Engine idle speed problems

[dag.boesterud]

The other day I had driven my 92 V8 4.2 about 4 km. Stopped her, and fired 
her up again after a few minutes. The idle speed was very low, the car 
almost died, and the engine had no power. Stopped the engine and started it 
again, everything was okay. 

The same thing happened to me again today, but today instead of stopping the 
car I managed to drive away, and when I got to my destination, the idle was 
fine. 

What could this be? Sticky idle valve? 

/Dag
92 V8 4.2