My tach settles around 900-1000 RPM if I let it warm and idle a bit. I don't recall seeing it drop much further below.
My brother (who drives it rarely) notices that there's not much go to my Tour lately even after stomping the gas pedel down. He said it use to have lots of go with less gas.
I'm beginning to suspect the fuel pump may be going from what others on this board has mentioned.