There ya go. Good deal.
You see, most don't use the science and theory of engine operations to recognize all the possibilities.
That puts a limit on ability to troubleshoot issues.
Of course intake air will show lower and larger differences at speed especially in the hot summer temps.
The air coming in cools the intake tract while at speed and settles the average cooling at a lower temperature.
As soon as the motor sets or idles a short time the engine bay heat is much higher than the outside air temperature. The average rises until the vehicle gets moving again, the engine bay airflow increases, temperature drops and air tube cools downward again.
It's all variable dynamics.
Good luck.

 

I do truly thank you for the help. been fighting it for quite some time, I am glad it was something fairly simple.