Why does my 07 Compass feel like it wants to stall when starting from stop?

What is your question?

It doesn't do it all the time. I notice it does it mostly when I'm almost at work (warmed up engine) There are no codes, no check engine light. The rpms go down and it feels like it wants to stall. One time it did stall. I took it to the shop, they drove it for 10 miles and said it didn't do it. They put it on the computer diagnostic and said nothing came up. I had all plugs replaced and the engine sensor. What could it be, I know I'm not hallucinating it. Thanks for any input.