2012 sport 5.0 motor.

At start up( cold or warm) the RPMs go to 2k for a few seconds, then to 1.2k for approx 25 seconds then settle at 750-800.

I have cleaned the throttle body and reset adaptive values with no change.

Had the intake off with ignition on while my wife stepped down in the pedal smoothly to check the butterfly movement. Seems a little stalled at the beginning of the sweep, but if it is, it's so minor that I'm doubting that's what I'm seeing.

Any thoughts?

 

2k seems high, but my wife's '11 RRS SC holds at a bit over 1k for the same period of time and then drops.

I think there is an air pump or some emissions deal in there until a temp is reached that does this. If hers sits for more than 10-15 minutes it does this.